Trang 1 FACULTY FOR HIGH QUALITY TRAINING GRADUATION PROJECT ELECTRONICS AND ELECTRONIC ENGINEERING TECHNOLOGY Ho Chi Minh City, December 2022DESIGN THE HIGH-SPEED CONTROL SYSTEM FOR T
OVERVIEW OF THE PROJECT
Problem
The importance of the industry in our country is growing due to rising social demands Modern devices must prioritize aesthetics, affordability, convenience, and user-friendliness To address these needs, investors, manufacturers, and engineers are tasked with developing technical models that align with the principles of Industry 4.0.
With the advancement of high-end technologies, there is a growing demand in factories for product manufacturing equipment like test tube shakers and bottle filling machines This need has prompted a focus on understanding device operation, control mechanisms, and model development Consequently, the team has chosen to explore the topic: "Designing a high-speed control system for synchronizing the rotary table with the linear motion lead screw."
Objectives of the topic
- Build a machine model with 3 X, Y, Z axes and a rotating circular disc axis
- Can communicate with devices of the following models: PLC Mitsubishi Q series, Servo Driver MR-J3-B, Servo, Motion CPU
- Controls operate precisely according to specified requirements
- Using software such as: GX Work2, GT-Designer3, GT SoftGOT2000, MT Developer2
Research subjects
+ Remaining hardware details: aluminum billet of axes, aluminum base, fixed aluminum bracket
+ Mitsubishi Q-series PLC controller (Q03DU)
+ MR-J3-B servo motor connected via SSCNETIII
+ The remaining devices: CB, Relay, magnet
Research methods
To successfully execute the project, the team researched various online resources, including Schneider company videos and servo manufacturer exhibitions They refined their approach by considering the initial objectives, relevant details, and the existing systems from previous courses Crucially, the enthusiastic feedback from their instructor provided valuable guidance and direction for their practical implementation of the topic.
Refer to practice and teacher's instructions to come up with many ideas
Research on servos, motion control and Motion CPU
Design drawings and process mechanical and electrical parts
Tweak the system to achieve what you want
Test run and get results
Conclusion and drawing of shortcomings as well as future development direction
THEORETICAL BASIS
Overview of project
The project utilizes a high-speed, precision tracking machine mounted on a circular disc This advanced system is capable of identifying and picking up objects from designated locations, then transporting them to specified areas It employs a mechanical control mechanism using three XYZ axes to facilitate accurate movement for both retrieval and release of items.
The XY axis movement is synchronized with the circular motion of the rotating disc axis As the Z axis reaches the rotation point on the disc's circular path, the XY axis begins to generate circular motion along the disc's circular axis through the linear movement of each axis.
2.1.3 Advantage and disadvantage of this project: a Advantages:
+ The technology can be extended to operate many different functions
+ Save time, operating manpower b Disadvantages
+ The project goal is only to handle problems for the high-speed synchronization of the experimental model
+ The level of synchronous speed should depend on almost of the mechanical system and the rated speed of used motors
+ The system operation is only to pick and place the objects without any recognization such as vision or barcode reading.
General introduction to PLC
A Programmable Logic Controller (PLC) is a semiconductor-based automatic control device that operates according to user-defined programs It utilizes programmable memory to store and execute control commands, functioning as a computer specifically designed for reliable operation in industrial settings.
Figure 2.1: All popular PLC series
To overcome the disadvantages of wired controllers (relay controllers), a PLC has been built to satisfy the following requirements:
+ Easy programming, easy to learn programming language
+ Compact, easy to maintain and repair
+ Large memory capacity to accommodate complex programs
+ Completely reliable in industrial environments
+ Can communicate with other smart devices such as computers, network connections, expansion modules
- Mitsubishi PLC Q series is a compact, high-performance PLC series It integrates new techniques that break the limitations of traditional programmers
The Multi-Processor technique enables simultaneous processing by four CPUs, significantly enhancing machine control, position control, and communication efficiency This advancement reduces program cycle scan time to just 0.5 to 2 milliseconds, optimizing overall performance Additionally, it offers users the flexibility to select control direction, perspective, and programming language, all integrated within a single platform.
- Suitable for high-end control applications
- Mitsubishi Q series PLC offers a wide range of solutions for different applications
- Applications of Mitsubishi PLC Q series: Beer and beverage industry, semiconductor technology, packaging, waste incineration
The Mitsubishi Q PLC family, an evolution of the AnSH series, offers unparalleled flexibility by allowing users to select and coordinate various components, including CPUs, communication engines, dedicated control modules, and I/O systems, all within a single communication framework This modularity enables customization to meet specific operational needs, whether for basic or advanced PLC CPUs, Motion CPUs, Process Controllers, or even PCs, with the capability to integrate up to four different CPUs in one system The Q series supports a range of control-oriented programming languages on a unified platform, making it suitable for both simple machine control and comprehensive equipment management Its design emphasizes flexibility and decentralization, establishing it as a versatile automation solution.
Figure 2.2: Types of PLC Mitsubishi a Main Features of Mitsubishi PLC Q Series:
- Processing speed up to 34ns/LD
- High-precision A/D-D/A unit, applied in temperature control, position control
- CIP (Chanel Isolated Pulse) input, built-in high-speed pulse counter
- Full support in MELSOFT software applications
- Full range of network applications such as: CC-link, MELSECNET-H,
- Online programming b The Advantages and Product Application of Mitsubishi Modular PLC:
+ Significantly improve system and machine performance
+ High-speed, high-precision data processing
+ Large memory, can store many separate work programs
+ Meet the strict technical requirements in the industry
+ Easy to change working mode
+ Save time for control work
+ Connect with other smart devices easily
+ Simplicity in the installation process is programming
Application of Mitsubishi Modular PLC
There are many applications of this PLC whether in industry or home appliances Several of them are as below:
For residential air conditioning systems, a straightforward control system is typically sufficient, utilizing a manual switch alongside a room thermostat and timer switches to regulate room temperature An ideal control solution for this application is the Mitsubishi Modular PLC.
The control unit in commercial air conditioning systems is managed by a thermostat that activates a relay or contactor, which in turn enhances the operation of compressors, fans, valves, and pumps Medium control unit operations are essential for safeguarding against abnormal temperature and pressure fluctuations, whether on the low or high-pressure side The Mitsubishi Modular PLC is commonly utilized in these applications.
+ Jet Towel Commercial Hand Dryer
The Area Traffic Control System (ATCS) optimizes urban traffic by synchronizing red lights across a city's road network This system efficiently manages traffic flow by analyzing vehicle counts and travel times For effective implementation of ATCS, the Mitsubishi Modular PLC is an ideal solution, ensuring precise control and improved traffic management.
Device CPU The common name for the Basic QCPU, High
Performance QCPU, Process CPU, Standby CPU, and General Application QCPU
Basic model of QCPU Q00JCPU, Q00CPU, and Q01CPU
Q02CPU, Q02HCPU, Q06HCPU, Q12HCPU, and Q25HCPU
Process Control CPU Q02PHCPU, Q06PHCPU, Q12PHCPU, and
Backup CPU Q12PRHCPU and Q25PRHCPU
Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCPU, Q03UDCPU, Q03UDVCPU, Q03UDECPU, Q04UDHCPU, Q04UDVCPU, Q04UDEHCPU, Q06UDHCPU, Q06UDVCPU, Q06UDEHCPU, Q10UDHCPU, Q10UDEHCPU, Q13UDHCPU, Q13UDVCPU, Q13UDEHCPU, Q20UDHCPU, Q20UDEHCPU, Q26UDHCPU, Q26UDVCPU, Q26UDEHCPU, Q50UDEHCPU, and
Q100UDEHCPU QCPU with built-in
Q03UDVCPU, Q03UDECPU, Q04UDVCPU, Q04UDEHCPU, Q06UDVCPU, Q06UDEHCPU, Q10UDEHCPU, Q13UDVCPU, Q13UDEHCPU, Q20UDEHCPU, Q26UDVCPU, Q26UDEHCPU, Q50UDEHCPU, and Q100UDEHCPU
High-speed general application QCPU
Q03UDVCPU, Q04UDVCPU, Q06UDVCPU, Q13UDVCPU, and Q26UDVCPU
Motion CPU Q172CPUN, Q173CPUN, Q172HCPU,
Q173HCPU, Q172CPUN-T, Q173CPUN-T, Q172HCPU-T, Q173HCPU-T, Q172DCPU, Q173DCPU, Q172DCPU-S1, Q173DCPU-S1, Q172DSCPU, and Q173DSCPU
Table 2.1: Types of CPUs PLC Mitsubishi
Table 2.2: Types of power supplies for CPU
Table 2.3: Types of Input Modules
Table 2.4: Types of Output Modules
AC Servo Motor
2.3.1 Introduction of AC Servo Motor:
An AC Servo Motor is a 3-phase electric rotating motor that utilizes permanent magnets, similar to those found in pumps and fans Unlike conventional motors, AC Servo Motors are equipped with advanced electronic components and sensors, including amplifiers, controllers, encoders, and monitors, which enhance accuracy and control This technological integration meets the demands of industrial production in the era of the 4.0 industrial revolution.
Figure 2.3: An AC Servo Motor from Mitsubishi
A servo motor is a specialized motor that utilizes feedback signals from an encoder to regulate its speed, torque, and position, ensuring optimal performance in various mechanical applications When faced with obstacles or impacts that impede the motor shaft, the feedback system enables the motor to adjust its torque and speed to accommodate the load Additionally, in the absence of a control signal, the servo motor maintains its current position, allowing it to return to its original alignment after any external disturbances.
2.3.2 Structure of AC Servo Motor System:
Structurally, Servo AC motor system is made up of 3 main components:
The controller consists of essential components like screens, buttons, and devices for information transmission and reception It effectively gathers data on speed, position, and torque, displaying the results on the main screen for user convenience This functionality allows users to easily customize parameters and configure the PLC to ensure the motor operates according to specific requirements.
This part has the function of receiving information in the form of code from the encoder They will then move back to the controller to display on the screen
Additionally, they have the capability to adjust actual outcomes, minimizing discrepancies during engine operation This highly automated feature is favored by customers, as it enhances accuracy to meet even the most stringent usage requirements.
Part 3 is considered the "heart" of an AC Servo Motor They are made up of 2 main parts, the motor and the product encoder
The motor consists of a rotor and stator, featuring secondary windings made of aluminum or copper Additionally, electromagnetic brakes function based on the principles of permanent magnet operation, enhancing their application in various settings.
Figure 2.4: Some parts of the product 2.3.3 Working principle of AC Servo Motor:
In principle, the servo motor is an independent device However, servo motor has practical significance only when operating in servo system
The servo operating mode utilizes closed-loop feedback systems, where the servo motor is activated by an electrical pulse signal (PWM) from the controller and is precisely regulated by an encoder.
When the motor operates, its speed and position are relayed to the control circuit via the encoder If any issue hinders movement and affects the desired speed and position, the feedback mechanism sends a signal to the controller The servo controller then compares this feedback with the command signal and makes necessary adjustments, ensuring the servo motor functions correctly to achieve optimal speed and position accuracy.
Servo Driver
A servo driver is a crucial component of a servo system that interprets control command signals, either pulse or analog, from a PLC It transmits these commands to the servo motor, ensuring precise operation in accordance with the given instructions Additionally, the servo driver receives feedback signals that provide continuous updates on the servo motor's current position and speed through the encoder.
The servo driver, often referred to as the servo amplifier, plays a crucial role in motion control systems by receiving signals from the controller and amplifying them This amplification enables the servo driver to provide the motor with precise voltage and current, ensuring optimal performance and efficiency.
The MR-J3-B servo amplifier enhances servo system performance by connecting to controllers through a high-speed synchronous network, directly reading position data for precise rotation speed and direction control By utilizing an advanced optical communication system, the MR-J3-B significantly boosts communication speed and noise resistance compared to previous SSCNET models Additionally, it supports a maximum wiring distance of 50 meters between electrodes, ensuring flexibility in system design.
Figure 2.5: MR-J3-_B Servo Driver Mitsubishi
The torque limit with a clamping circuit is implemented in the servo amplifier to safeguard the main circuit's power transistor from overcurrent due to rapid acceleration, deceleration, or overload Furthermore, the torque limit value can be adjusted to the desired setting within the controller.
This new series features USB communication capabilities, allowing users to connect a PC with MR Configurator installed for tasks such as parameter setting, operational testing, status monitoring, and gain adjustment.
The MELSERVO-J3 series servo motor features real-time auto-tuning, allowing for automatic adjustments of servo gains based on machine requirements Equipped with an absolute position encoder boasting a resolution of 262,144 pulses per revolution, this servo motor ensures precise control for enhanced performance.
Incorporating a battery into the servo amplifier creates a reliable absolute position detection system, eliminating the need for a home position return during power-on or alarm situations, as the home position only needs to be set once.
Figure 2.6: The figure indicate the meaning of Servo Driver’s name
Figure 2.7: The information contained on the Servo Driver's label
2.4.3 SSCNET (Servo System Controller Network):
Servo technology has seen significant advancements, particularly with SSCNET, which enables high-performance and high-accuracy devices that surpass the capabilities of traditional pulse train and analog commands Conventional pulse-train commands are limited by their pulse frequency, making them inadequate for high-speed and precise control, while analog commands suffer from issues such as line noise, voltage drops from cable length, and temperature drift.
SSCNET effectively addresses operational challenges by delivering high-speed and accurate performance Its advanced serial communication system facilitates seamless integration of servo motor synchronous control and absolute-position systems, while the one-touch connector streamlines wiring processes SSCNET is available in two types of cables: the metal cable SSCNET/SSCNETII and the optical fiber cable SSCNETIII.
+ For CN1A connector, connect SSCNET cable connected to the controller in host side or servo amplifier
+ For CN1B connector, connect SSCNET cable connected to servo amplifier in lower side
+ For CN1B connector of the final axis, put a cap came with servo amplifier
- Powerful Device with Synchronous Communication
The conventional pulse-train command presents challenges for synchronous startup and high-accuracy two-axis interpolation due to the asynchronous operation of the servo amplifier and motion controller.
+ SSCNET realizes powerful functionality of the devices (ex printing machines, food-processing machines, machine tool, etc.) that require accurate synchronization
- Advantages of Central Control with Network
+ SSCNET can exchange large volume of data between the controller and servo amplifier in real time
+ Servo parameters can be set from the personal computer connected to the controller when Motion controller is in use
+ Motor speed, current position and voltage value of each axis can be monitored with the digital oscilloscope function
- Easy Structure of Absolute System
An I/O module is essential for transmitting and receiving ABS data to establish an absolute system using a pulse-train command Additionally, proper wiring is crucial between the I/O module and the servo amplifier to ensure effective communication and functionality.
SSCNET eliminates the need for wiring, making it simple to establish a complete system With no requirement for home-position return operations, users can quickly initiate operations immediately after powering on, even when managing multiple axes.
SSCNET ensures high accuracy and reliable communication in data transmission In the event of an error, the system discards the erroneous data and continues with the next set of normal data.
+ SSCNET can be connected only by inserting the dedicated cable into connectors
No more complicated wiring is necessary
Overview of Synchronous Control
"Synchronous control" can be achieved using software instead of controlling mechanically with gear, shaft, speed change gear or cam etc
Synchronous control aligns movement with the input axis, including the servo input axis, command generation axis, and synchronous encoder axis This is achieved by configuring the parameters for synchronous control and initiating it on each output axis.
Figure 2.9: Virtual mechanical system overview
2.5.2 List of Synchronous Control Module:
Figure 2.10: Overview of virtual mechanical system
Synchronous control enables the management of one or more trajectory engines that operate in conjunction with the main engine's movement This advanced system utilizes a virtual mechanical framework to achieve synchronized control of the engine through components such as camshafts, gears, and clutches.
The MT Developer2 synchronous control interface allows for comprehensive monitoring of all synchronous control monitor data, including the rotation direction of the main input axis, main shaft sub input axis, auxiliary shaft, and output axis (cam axis feed current value).
The main shaft module generates an input value by combining two input axes—the main and sub-input axis—via the composite main shaft gear.
32 composite input value can be converted by the main shaft gear that provides the deceleration ratio and the rotation direction for the machine system, etc
Name External Shape Function description
+ The input axis on the main side of the main shaft module
+ The reference position on the main shaft
Main shaft - Sub input axis
+ The input axis on the sub side of the main shaft module
+ It is used to compensate for the position of the main shaft main input axis
Utilize the primary input axis from one of the available servo engines, such as a conveyor belt, lead screw, or turntable, to control additional components The auxiliary mechanism will operate in accordance with the movements of the installed servo axis, following specific parameters configured within the system.
A virtual servo axis operates solely within the software environment, allowing for the display and control of movements without being physically present in the real system This virtual axis synchronously rotates the main axis, while other engines and structures adjust their movements in accordance with the virtual servo engine's actions.
The auxiliary shaft module generates an input value from the auxiliary shaft, which is then transformed by the auxiliary shaft gear This gear not only provides the necessary deceleration ratio but also determines the rotation direction for the machine system.
Name External Shape Function description
Auxiliary shaft axis + The input axis of the auxiliary shaft module
+ The converting auxiliary shaft travel value is transmitted by the setting gear ratio
+ The auxiliary shaft travel value is transmitted by the clutch ON/OFF
+ The composite travel value of the main shaft and the auxiliary shaft are transmitted
The output shaft for synchronization is driven by a cam mechanism, which utilizes a cam plate to adjust the position of the story linked to the servo engine based on the designated orange plate This cam plate generates rotation corresponding to the pulse count with each spin of the orange disc.
The operations are performed with Cam functions
+ 2 -way operation: AC operating with a fixed Cam journey series
+ Operating in: Cam reference position is updated each cycle
+ Linear operation: linear operation (Cam No 0) in the cycle according to the journey ratio is 100%
Figure 2.12: The chart illustrate the three different function of Cam data
The output axis is regulated by a current input value, which is derived from the camshaft's position during each cycle through the Cam data conversion process.
Motion SFC programming language
SFC stands for sequential function chart, also known as sequential function chart, is a graphic programming language (not based on text) used for PLC programming controllers
Machine operations are overseen by the PLC CPU, while motion SFC programs are initiated and halted by the motion CPU through commands from the PLC This setup introduces a delay, as the time from when command conditions are set to when commands are executed is limited by the number of sequences required for a single scan Consequently, this delay hampers applications that require high responsiveness and minimal tact time.
The Q Series motion controller utilizes a Sequential Function Chart (SFC) to effectively manage machine operations Additionally, it allows for the execution of programs in response to interrupts from external sensors, enhancing operational control and responsiveness.
The figure below is an SFCS (SFC start) command used to start the specified motion SFC program
Figure 2.13: The command to call Motion SFC program
+ Applicable CPU No first I/O No 1 ÷ 16 + The values actually specified are as follows
Example: CPU No.2: 3E1H, CPU No.3: 3E2H, CPU No.4: 3E3H (n2) + Motion SFC program N0 To be started
+ (D1+0): Device for which 1 scan is turned ON when command start receipt processing is complete
+ (D1+1): Device for which scan is turned ON when command start receipt error is complete (D1+0 also turns ON when error complete)
(D2) + Device in which completion status is stored
Figure 2.14: The table shows the functions of the SFCS command
The Motion SFC Program is constituted by the combination of start, steps, transitions, end and others are shows below
Figure 2.15: Structure of Motion SFC program
The above Motion SFC program to be started performs the following operations
(1) The step (F0) is activated and the operation specified with the step (F0) is executed (positioning ready) A step in such an active state is called an active step
The system checks if the specified condition for the transition (G0) is enabled to determine if the positioning program can be initiated Upon completion of this condition, the active step (F0) is deactivated, and the next step (K0) is activated, initiating the servo program (K0).
(3) The operating completion of the step (K0) (positioning completion of the servo program K0) is checked, and control transits to the next step at operating completion (completion of condition)
(4) With the transition of the active step as described above (1) to (3), control is executed and ends at END
+ Easy to fix problems, find faster technical errors
+ Program design faster and repeated retail details, saving time
+ Can be accessed directly to the logic section to see the location of the defective device
- Limitations: The owner is suitable for some specific applications.
Overview related software
GX-Works 2 is an upgraded software solution from Mitsubishi, designed to enhance the capabilities of PLC programming It offers improved visual interfaces and smoother operations, along with expanded support for additional programming languages, including Function Block Diagram (FBD) and Sequential Function Chart (SFC).
Figure 2.16: The interface of GX Works2 software
GX Works2 is a programming tool used for design, debugging, and maintenance of the program on Windows
GX Works2 has improved the function and ability to manipulate, with easier use features when compared to the existing GX Developer
GT-Designer 3 is a specialized software for interface design and control programming for the HMI screen of the manufacturer Mitsubishi The software is in the
GT Works3 software package, which is widely distributed by Mitsubishi to users
Figure 2.17: The interface of GT-Designer3 Software 2.7.3 MT-Developer2 software:
MT Developer 2 software is a software from Mitsubishi used to program Mitsubishi
Motion CPUs Besides, it makes it easier to write programs for the SFC programming language
The MT Developer2 synchronous control interface allows for comprehensive monitoring of all synchronous control monitor data, including the rotation direction of the main input axis, main shaft sub input axis, auxiliary shaft, and output axis, specifically tracking the cam axis feed current value.
Figure 2.18: The interface of MT-Developer2 Software
HARDWARE DESIGN
Introduction to the project
The synchronous model of the construction group is an experimental model, so the model needs to be designed and constructed to ensure the following requirements:
Capable of synchronizing 2 motor axes with the circular disc control shaft, easy to control, stable at any speed
Achieve synchronization at high speed
Solid structure, removable, safe for the operator
The servo synchronous model comprises two primary components: the mechanical part and the electrical part To achieve a compact and aesthetically pleasing design, it is essential to calculate the model's volume limits and dimensions To ensure timely completion, the project is divided into two phases: the construction phase, which encompasses both the mechanical and electrical components.
Configuration option – DAQ
Connecting devices such as computers, I/O modules directly via cables or wires will bring many significant benefits such as:
On the other hand, this configuration cannot be applied to objects such as:
A large system has too many connections for input and output devices
For systems requiring flexible mobility, using long wires from the PC to the sensor can be impractical and costly, especially in large setups Additionally, the distance or movement of the object may hinder effective communication with the PLC.
Using Ethernet cables brings many things to devices such as:
Reduce noise, increase signal accuracy, output quality from devices like sensors
Ability to move to different locations for large networks
Far/Long distance between PLC/PC to sensor/actuators
Cannot be applied to complex network system
The system is designed as a compact unit for construction site operation, making a centralized configuration the most effective choice This design allows for direct connections between sensors, minimizing equipment costs and reducing interference In contrast, a decentralized I/O configuration, while potentially meeting certain requirements, fails to capitalize on the benefits of a centralized setup It can result in unnecessary expenses related to transportation and maintenance, as well as increased interference from long wiring runs.
Electrical part design
Figure 3.1: Structure of the whole system block diagram
Functions of each block in the system:
Power Supply Block: There are two types of power used in the system
+ The 220VAC source will supply power to all Servo Drivers used in the system (3 straight axes and 1 circular axis) and the PLC
+ 24VDC source as a source of control signals for control circuits such as sensors and Forced Stop of Motion CPU (EMI)
The Main Processing Block is essential for generating signals that enable motor blocks to perform calculations and synchronize their operations It facilitates communication with peripheral devices like sensors, outputs pulses, and controls motors Central to this block is the Motion CPU (Q172DSCPU), which utilizes SFC language for the synchronous processing of motors.
The Synchronous Servo Motor Block is designed to receive and interpret data from the main block, enabling the synchronized control of multiple motors This system effectively manages three motors simultaneously, all utilizing the same MR-J3 Driver type for optimal performance.
Disk Servo Motor Block: This block controls the rotation of the platter and is also the main motor to regulate the three programmed synchronous motors
The Sensor Block features three APM-D3A1 proximity sensors for each axis, enabling precise setting of the upper limit, lower limit, and HOME position In contrast, the circular axis is equipped with a single sensor to identify the HOME position.
The CPU station comprises several essential components, including the Base CPU, Power Supply Module, Main PLC, Motion Module, and I/O Module The accompanying image illustrates the devices integrated into the system, arranged sequentially to create the CPU station.
Figure 3.2: Name and arrangement of modules on the station a Base CPU
Number of slots: 9 I/O slots và 1 power supply slot
Table 3.1: The information of Base Q38DB
Over-voltage/over-current protection:
Table 3.2: The information of Power Supply Module Q61P c Q03UDCPU:
Number of I/O device points 8192 points
Number of I/O device with code (HEX) X/Y0000 to 1FFF
Basic operation processing speed (LD instruction) 20ns
Multiple CPU high-speed communication peripheral connection ports USB and Ethernet
Table 3.3: The specification of Q03UDCPU Module
- Providing high-speed communication between multiple CPUs
- Shorten the fixed scan interrupt time, high precision device
- The minimum interval of the fixed period interrupts the program is reduced to 100 s
- The high-speed signal can be accurately obtained, contributing to the device's higher precision
- High speed and high precision machine control by multi CPU
- By parallel processing of the linear and multi-CPU high-speed communication of the parallel control program, the high-speed control
- Multi CPU high-speed communication cycle and motion control synchronization, so it can achieve the maximization of computing efficiency
- Ensure high speed and high accuracy of the machine control d Q173DSCPU:
The CPU Motion Q173DS module enables seamless communication with the servo amplifier, allowing for the downloading of servo parameters, activation and deactivation of the servo amplifier, and execution of position commands and virtual cam operations This is achieved through a direct connection using an SSCNET cable.
1) 7-segment LED Indicates the operating status and error information
2) Rotary function select 1 switch (SW1)
(Normal operation mode, Installation mode, Mode operated by ROM, etc)
• Each switch setting is 0 to F
(Note): Switch setting of factory default
4) RUN/STOP switch Move to RUN/STOP
RUN : Motion SFC program (SV13/SV22)/Motion program (SV43) is started
STOP : Motion SFC program (SV13/SV22)/Motion program (SV43) is stopped
Input to stop all axes of servo amplifier in a lump EMI ON (opened) : Forced stop
EMI OFF (24VDC input) : Forced stop release
6) SSCNET CN1 connector Connector to connect the servo amplifier of system 1
7) SSCNET CN2 connector Connector to connect the servo amplifier of system 2
8) Serial number display Displays the serial number described on the rating plate
9) Module mounting lever Used to install the module to the base unit
10) Module fixing hook Hook used to fix the module to the base unit (Auxiliary use for installation)
11) Module fixing screw Screw used to fix to the base unit (M3×13)
12) Module fixing projection Hook used to fix to the base unit
16) Internal I/F connector Connector to connect the manual pulse generator /
Incremental synchronous encoder, or to input the input signal/mark detection input signal
(Voltage-output/open-collector type, Differential- output type)
18) Battery holder Holder to support the battery (Q6BAT)
19) Battery cover Cover for battery (Q6BAT)
Table 3.4: The component table of Q173DSCPU Module
Number of control axes Up to 32 axes
0.22ms/ 1 to 4 axes 0.44ms/ 5 to 10 axes 0.88ms/ 11 to 24 axes 1.77ms/25 to 32 axes SV22
0.44ms/ 1 to 6 axes 0.88ms/ 7 to 16 axes 1.77ms/17 to 32 axes Interpolation functions
Linear interpolation (Up to 4 axes), Circular interpolation (2 axes),
Number of positioning points 3200 points (Positioning data can be designated indirectly)
Peripheral I/F USB/RS-232/Ethernet (Via PLC CPU)
Number of output points 32 points Watch data: Motion control data/Word device
Total 256 points (Built-in interface in Motion CPU (Input 4 points) +
Communication method SSCNET III/H, SSCNET III
Table 3.5: The specification of Q173DSCPU
Table 3 6: The specification of Module Input QX42
46 Figure 3.6: The external connection diagram of QX42
Table 3.7: Pin-Outs of QX42
Table 3.8: The specification of Module Output QY22
Figure 3.8: The external connection diagram of QY22 3.3.2.2 Servo Drivers and Servo Motors selection:
To meet the control requirements of the group model set out: accurate control of position at high speed group selecting Mitsubishi engine and driver set as follows:
Driver’s name Servo motor’s name
HG-KR053 HF-KP13B HF-KP053
Each capacity of the Linear engine is paired with a specific Driver, featuring a 200W Servo motor for the X-axis and 100W and 50W motors for the other three axes Due to the significant mass of the X-axis, a distinct motor type is required to ensure effective lead screw rotation.
Servo motor series: low inertia, medium and large capacity
Power supply: 0.9A 3-phase or 1-phase 200 to 230VAC, 50/60Hz
Servo motor series: low inertia, medium and large capacity
Power supply: 0.9A 3-phase or 1-phase 200 to 230VAC, 50/60Hz
Specification of Servo Motor in X-Axis:
Figure 3.10: Servo Motor of X-Axis
Rated speed: 3000r/min (max 6000r/min)
Specification of Servo Motor in Y-Axis:
Figure 3.11: Servo Motor of Y-Axis
Rated speed: 3000r/min (max 6000r/min)
Specification of Servo Motor in Z-Axis:
Figure 3.12: Servo Motor of Z-Axis
Rated speed: 3000r/min (max 6000r/min)
Specification of Servo Motor in Disk-Axis:
Figure 3.13: Servo Motor of Disk Axis
Rated speed: 3000r/min (max 6000r/min)
Configuration: Covered type, front terminals
An electromagnet consists of a coil of wire, typically wrapped around an iron core, although it can also be wound around an air core, known as a solenoid When connected to a DC voltage or current source, the electromagnet generates a magnetic field similar to that of a permanent magnet The strength of the magnetic flux density is directly proportional to the current flowing through the wire, while the polarity of the electromagnet is dictated by the direction of the current To identify the north pole of the electromagnet, one can use the right-hand rule.
Figure 3.16: KK-P20/15 24VDC 3KG Lifting Solenoid Electromagnet
In the system are using 3 Circuit Breakers, in which:
- NF30-SS is used to switch Servo Driver
- MU104A is used to switch PLC and power supply 24VDC
- CB30-BA controls the output of the power supply 24VDC
Figure 3.17: Circuit Breaker NF30-SS-
+ Model: NF30SS2P20A + Voltage rating: 600VAC + Number of poles: 2-pole + Current rating: 20A
+ Model: MU104A + Voltage rating: 230/400V + Current rating: 4A
Figure 3.19: Circuit Breaker CP30-BA
+ Model: CP30-BA 2P 2-M 5A + Rated block capacity: 2.5Ka + Rated Voltage: AC250V/DC125V + Number of poles: 2-pole
Figure 3.21: Specification of Sensor APM-D3A1
Figure 3.22: Diagram of equipment layout
Figure 3.23: Diagram of communication between drivers
Figure 3.24: Wiring diagram of the dynamic circuit
Figure 3.25: Wiring diagram from 24VDC source to devices
Figure 3.26: Wiring diagram of sensors on each axis
Figure 3.27: SSCNET connection diagram of servo drivers 3.3.4 Construction of electricity:
After calculating and selecting equipment for the machine system and learning, arranging equipment, designing a wiring diagram, our team conducts energizing construction according to the following steps:
Step 1: Take the encoder wires, dynamic wires for motors, sensor wires from the mechanical part to the control modules neatly to ensure safety and aesthetics for an automation machine
Step 2: Arrange electrical equipment and electrical troughs in the system in a beautiful and reasonable manner, then drill holes and fix electrical equipment to the aluminum trough
Step 3: Wire the devices from the system according to the wiring diagram in the order from top to bottom according to the figure in section 3.3.3 (the power cord to the devices to the signal wire and Encoder wire, the motor's driving wire )
Step 4: Check wire cooling by EPM according to the wiring diagram In order to ensure that the system operates stably according to the pre-prepared structure, avoiding small to large errors that affect the equipment
Step 5: After making sure the safety check, wire it correctly Power on the system, check the device is still working or not.
Mechanical part design
The Servo synchronous model is designed to control four motion axes, consisting of one circular axis and three linear axes that operate along the Oxyz axes Consequently, the mechanical requirements will encompass specific components essential for optimal performance.
The system consists of three linear axes, each equipped with a lead screw unit for high-speed rotation, ensuring continuous speed translation during operation To facilitate this, three servo motors are required, supported by sturdy bases to handle the weight of the motors and mechanisms during movement It is crucial that the coupling between the motor and the lead screw's threaded nut is both rigid and precise to prevent deflection during rotation Additionally, the lead screw and motor must have matching contact sizes to ensure reliable engagement of the high-speed copper components, preventing any potential breakage.
To ensure stable operation and prevent eccentric movement, it is essential to mount a fixed circular disc made of Plexiglass on the servo The disc should be positioned with its center face facing upward, requiring the selection of an appropriate lead screw that allows the motor to lie horizontally while maintaining the disc's alignment Additionally, the motor should be oriented vertically to facilitate convenient and aesthetically pleasing wiring.
- Limit motion sensors are required
- The supporting structure must be very sturdy and withstand the weight of 3 Linear Servos during movement
Figure 3.28: X-axis support base assembly and machined rear stand
The X-axis is machined horizontally along the tabletop and is raised by 3 group posts to stabilize the object when moving The X-axis uses a lead screw which is rotated by a Servo motor 200W HF-KP23G1 with a pitch of 10mm of the lead screw On the designed lead screw holder, there will be enough space to wire the Y, Z axes
In addition, the X-axis is equipped with 2 more sensors to limit the distance between the sides to 410mm and 1 sensor to confirm the HOME position (the landmark to 0)
Figure 3.29: The Y axis is attached to the moving X axis
The machined Y-axis operates perpendicularly to the X-axis, utilizing a lead screw driven by a 50W Servo motor HG-KR053 with a 12mm pitch Additionally, there is designated wiring space for the Z-axis to run alongside the X-axis.
In addition, the Y-axis is equipped with two sensors that limit the travel on both sides of 172mm and a sensor that confirms the HOME position (the landmark to 0) c Axis Z:
Figure 3.30: Mount the Z-axis on the system
The Z axis is vertically machined and connected to the Y axis of the motor, featuring a post that runs parallel to it for magnet support This Z axis is driven by a 100W HF-KP13B Servo motor utilizing a lead screw with a pitch of 6mm.
In addition, the Z-axis is equipped with 2 sensors to limit the side travel to 45mm and a sensor to confirm the HOME position (the landmark is 0) d Axis Disk:
Figure 3.31: Mount the D-axis (Axis Disc) on the system
The rotating disc shaft is precisely machined to ensure the disc remains horizontal while the servo motor is mounted on the tabletop A 90-degree angled gearbox is utilized to connect devices that fulfill specific requirements This setup features a 50W HF-KP053 Servo motor paired with a 1/10 gearbox for optimal performance.
The circular disc shaft features a sensor that identifies the HOME position, designated as the landmark 0 To prevent vibration and potential damage from the motor's high-speed rotation, our team requires a clamp to secure the rotating shaft between the motor neck and the table top.
Figure 3.32: Mount the pillar on the system
The workpiece column is designed to ensure that the Z-axis travel distance is optimized for efficient object handling Additionally, it features rounded edges that facilitate the placement of objects on the cylinder.
Result
The robust construction of the mechanical components guarantees simultaneous movement along three coordinate axes, ensuring high-precision printed circuit milling without any deflection.
The electrical components play a crucial role in safeguarding both the operator and the equipment within the system Proper wiring and an organized layout of the electrical cabinet are essential for the functionality of automated machines while also enhancing their aesthetic appeal.
The synchronous control model of 3-axis Linear Servo and 1-axis of rotary disk designed and constructed by our team includes 3 main parts:
+ The mechanical part: includes 3 axes X, Y, Z and a rotating disc axis
+ Electrical part: includes equipment arranged and installed inside the electrical cabinet
+ Control part: manual pulse generator is responsible for activating the machine
Figure 3.33: Some pictures of hardware design result
CONTROL PROCESS
Overall operation of system
4.1.1 State diagram of system operation:
Figure 4.1: State diagram of system operation 4.1.2 Explanation to state diagram:
The given state diagram indicates that after turning on all axes servo, the operation state will be in waiting condition until operator selects control type to operate the system
In the initial control phase, the operator manually ensures that all four axes pass through the zero point before activating the home button Once the home completion indicator is activated, the operator can perform both manual and automatic control operations.
Manual control requires the operator to directly engage buttons to manage the system's movements Prior to activating the buttons, it is essential to set the positioning address and speed for each axis.
The HMI screen must display values within an allowable range for setting the position address and speed of each axis Once the selected movement is completed, the operator can proceed with the next action, such as initiating another control operation or turning off the system by pressing the "Servo off" button Additionally, during the motion process, if any RLS, FLS, or overspeed signals are detected, an alarm will activate immediately to alert the operator and halt the current motion until all errors are resolved.
In automatic control operations, the system must wait for a home completion signal before proceeding, ensuring synchronization among four axes for the rapid picking and placing of objects with high speed and precision Once the task is completed, the synchronous operation halts, allowing the operator to initiate a new control or power down the system Additionally, after completing the synchronous control process, the system can automatically return to its zero point using an integrated automatic function block, facilitating a seamless transition for future operations from the original position.
Synchronous operation
Figure 4.2: The flowchart of main synchronous operation
Figure 4.3: The flowchart of initial operation
Figure 4.4: The flowchart of electromagnet operation
Figure 4.5: The flowchart of speed change operation
The flowchart illustrates that once all axes servo statuses and the zero pass signal are confirmed, the initial operation can begin its programming until it receives a completion signal Additionally, the synchronous motion, guided by cam data, can be activated, with the electromagnet's operation contingent on its set position during this synchronization Ultimately, when the synchronous control signal is turned off, the main operation successfully completes its mission in a synchronized manner.
The zero pass signal at the start of the main operation simplifies the ignition operation's starting block, effectively establishing the home position for all four axes Once the home position is confirmed, the system activates synchronous control start data and main clutch command data, crucial for synchronous motion operation After completing these settings, the counter number and initial speed are established, serving as the foundational conditions for subsequent operations.
When the synchronous motion begins, three linear lead screws move towards the designated address to pick up an object while the rotary table spins The process continues until the address value is confirmed, triggering both the counter and the electromagnet to secure the selected object for placement Speed adjustments can only be made after the counter number changes Once the object is positioned correctly, the electromagnet deactivates to release the object safely To ensure ongoing synchronous control, the system continuously checks the control signals to determine whether to initiate or complete the operation Upon completion, all four axes return to their home position, resetting the counter and current speed values.
To begin with the speed change operation, this process will start with the initial speed value recommended in the initial operation for setting up the synchronous motion
To modify its current value, the system relies on the fluctuating counter number to adjust the speed value until it reaches the maximum allowable limit When the counter number remains stable in the short term, the system continues operating at the current speed while awaiting a change in the current value If the counter number exceeds the predefined range, the synchronous control operation will deactivate, causing all axes to return to the zero point and resetting both the counter number and current speed value.
Programming solution
As can be seen in below picture, it shows that the programming control will start from Q PLC CPU to activate the command sent to Q motion CPU for program execution
Figure 4.6: The structure ò function command SFC Motion program
The positioning parameters outlined in the example indicate that these functions can only be activated through motion CPU control Subsequently, the servo amplifier is able to respond to the data received from the motion CPU command, enabling the servo motor to operate according to the design specifications.
Figure 4.7: Example of commanding SFC Motion program
In the given comparison, it illustrates for the reason that the following programming solution will use the methodology of motion SFC (Sequential Function Chart) to control
The synchronous process in programming often leads to delays due to the time spent scanning and executing commands sequentially In contrast, utilizing advanced programming control allows for the activation of steps based solely on transition conditions, significantly enhancing execution speed through precise feedback signals This project aims to optimize the synchronous operation of multiple axes at high speeds, making the SFC program method a more efficient choice.
In this first part, the main purpose is to create project and the connection between the PLC CPU and Motion CPU for data exchange to each other
In the GX Works 2 software:
Step 1: Start the new project creation
Figure 4.8: The original interface of GX Work2
To ensure optimal performance in your current project, it is crucial to identify the appropriate type of series that aligns with the selected hardware Subsequently, the programming language should be chosen accordingly, as illustrated in the accompanying diagram.
Step 2: Set up the PLC parameter
70 Figure 4.9: Setting value for PLC parameter
Figure 4.10: Communication between PLC CPU and Motion CPU
To properly configure the I/O Assignment, it is essential to designate the PLC type and incorporate a new module, ensuring that it adheres to the designated practical position for accurate I/O address correction.
In a Multiple CPU configuration, two key tasks are essential: selecting the PLC number and setting up shared memory Initially, it is important to determine the current number of utilized PLCs based on prior I/O configurations and then input this value into the No of PLC field Additionally, shared memory serves as a crucial intermediary link between the CPUs, facilitating communication and coordination.
The PLC system utilizes two CPUs: CPU 1 (Q03UDCPU) and CPU 2 (Motion CPU - Q173DSCPU) For instance, when the M3072 bit is activated by CPU 1, it sends a signal to CPU 2 Subsequently, CPU 2 receives this data and records the M3072 bit during its main cycle processing, ensuring effective communication and memory sharing between the two CPUs.
In the MT Developer2 software:
Step 1: Start the new project creation
Figure 4.11: The original interface of MT Developer2
To ensure proper connectivity with the PLC CPU, the operator must first verify the series and type of Motion CPU in use Next, the appropriate OS type and operation method will be installed as specified for the project Additionally, other settings should align with the operational requirements of the project.
Step 2: Base setting for basic setting
Figure 4.12: Base setting of MT Developer2
In this context, the primary task involves choosing the number of slots in the Main Base, which must align with the practical hardware specifications This selection serves as the foundational condition for configuring the system.
Step 3: Multiple CPU setting for shared memory devices
Figure 4.13: Setting value for PLC Motion parameter
The image illustrates the Multiple CPU configuration for a PLC CPU, indicating that the memory device will be shared across the installation To configure the shared memory device, use the "Import Multiple CPU Parameter" option and select the file for the designated PLC CPU (CPU 1) Finally, by clicking the highlighted link below the settings, you can access the shared memory devices linked to CPU 2.
Step 4: SSCNET setting for using corresponding servo driver
Figure 4.14: SSCNET Setting for servo driver MR-J3
In this project, the use of MR-J3 servo drivers necessitates the selection of SSCNET III for communication, as this is the only compatible option In contrast, MR-J4 servo drivers utilize a different communication type This fundamental setting serves as the initial step for configuring SSCNET with the specified servo motors.
Figure 4.15: The interface of system configuration in MT Developer2
To ensure optimal configuration, the operator must identify the existing hardware types in the main base for installation in the motion slot settings In this project, the 8-slot main base will accommodate the PLC CPU (Q03UDCPU) in the first slot, the Motion CPU (Q173DS) in the second slot, the Input module (QX42) in the third slot, and the Output module (QY22) in the final slot.
Figure 4.16: The interface of SSCNET configuration
This project involves the operation of four axes, each controlled by MR-J3 servo drivers To access detailed information about the amplifier settings, users can simply click on the selected axis to turn on the amplifier settings.
Fixed parameter: Set the fixed parameter for each axis and their data is fixed based on the mechanical system
Figure 4.17: Setting Servo parameter in MT Developer2
In the given picture, there are five significant parameters explained as following:
+ The command unit per axis for positioning control including mm/inch/degree/pulse units
+ In this project, there are two motion types such as linear motion and rotary motion, so the unit could be “mm” for linear motion and “degree” for rotary motion
+ The number of feedback pulses per motor revolution determined by mechanical system
+ In this project, because of MR-J3 servo driver use with 18-bit resolution, so the number of pulses per revolution could be 262144 pulses
Movement Amount/ Rev The movement amount per motor revolution determined by mechanical system
Upper Stroke Limit Upper limit value for machine travel range
Lower Stroke Limint Lower limit value for machine travel range
Home Position Return data: Set the data to return home position
Figure 4.18: Setting parameter in Home Position Return Data
In this context, the key parameters are the "Home Position Return" Speed and Creep Speed The home position return speed is activated upon receiving a command to initiate the home position return process, and once the zero pass signal is attached, the creep speed takes over, adjusting the speed to ensure a smooth transition to the zero point This operation concludes only when the home position completion signal is activated.
In case of the current position is in the different direction to go to the zero point, the
“Home Position Return” Retry function starts working until the home position return direction is correct with the setting
Figure 4.19: Setting parameter in Parameter Block
The parameter block is essential for establishing common parameters in servo data control systems In this project, two parameter blocks are utilized to manage both linear and rotary motion, allowing for effective interpolation of control axes Notably, the speed limit value is defined within an acceptable range for these control axes, ensuring safe speed settings and operation of the control system for optimal protection.
Figure 4.20: Setting signal types in Servo External Signal Parameter
In this project, the external signal system utilizes the DI3 input of the servo amplifier to manage the switching signal, leveraging the capabilities of the hardware effectively.
78 device and its specification, the type of the contact will depend on the device characteristics to decide to select whether normally open contact or normally closed contact
Figure 4.21: Setting parameter in Command Generation Axis
Synchronous operation calculation
Figure 4.43: The flowchart of overall the research method
93 4.4.1.2 Process and analyze the pick and place co-ordinates:
Figure 4.44: The flowchart of the process of the pick and place coordinates
4.4.1.3 Process and analyze the synchronous motion at high speed:
Figure 4.45: The flowchart of synchronous motion at high speed
The flowchart illustrates the initial steps for surveying and gathering fundamental information necessary for analysis It emphasizes the importance of researching theoretical foundations, including equations related to two types of motion and cam operation, to effectively design synchronous motion systems.
Following the synthesis, the next crucial step is practical data collection This project relies heavily on the integration of theory and experimentation, making the actual surveyed data essential for validating the precision of the conducted experiments.
In the third step, the initial calculations for the coordinates involved in picking and placing objects will commence using theoretical formulas alongside actual data Once satisfactory data is obtained, it will be utilized as output for this step and subsequently imported into the CAM operation for high-speed testing in the fifth step The primary objective of the speed test process is to determine the maximum speed value for each cycle of the pick and place operation for every object.
Process and analyze the pick and place co-ordinates:
To effectively synchronize the movements of a rotary table with two linear lead screws, it is crucial to establish a formula that accurately identifies the coordinates on both the X and Y axes This formula simplifies the process of achieving precise synchronization between the different motions In this project, we will implement four distinct speed levels, necessitating the calculation of velocities for the linear motions as they follow the rotary table at specific points By analyzing the calculated velocities at various rotation speeds, we can determine the maximum speed suitable for synchronous motion in this project.
Following the calculations, the next crucial step is to conduct a precision test through experimentation to determine the error margin between the calculated and actual data In this project, values should ideally be less than five percent of the radius These satisfactory values can be categorized into two types: those that fall within a range of three to five percent of the radius, which can be used for following the selected point, and those less than three percent of the radius, which can be used for object picking The primary objective of this initial experiment is to effectively distinguish the satisfactory data derived from the calculations for practical application.
The final experiment aims to accurately verify the placement of objects using the data obtained from the initial experiment Given the necessity for precision in the placing operation, selecting the correct data is crucial This will result in a comprehensive list of high-precision data for object placement, facilitating the design of synchronous motion across various creations without compromising accuracy.
Process and analyze the synchronous motion at high speed:
To ensure the success of the project, it is crucial to validate the precise coordinates obtained from experiments through high-speed motion testing This process aims to achieve two primary goals: precision and high-speed synchronization.
To create a cam curve, it is essential to connect motion with selected data A series of speed tests will be conducted to ensure the stability of the synchronous model and its precise operation until the maximum speed is reached Once stable operation at high speeds is confirmed and the peak speed value is achieved, the results will be validated for the project.
Assuming that point M moves in the positive direction with velocity ω, P is the projection of M onto the Ox axis, we have:
+ After the time interval t, M will have angular coordinates + t
+ Set A = OM, we get x = Acos(ωt + φ) + 0, where A, ω, φ are constants
Since the cosine function is a harmonic function, the point P oscillates around the zero point on the circular motion Hence, there would be following equations:
+ a is center point of X-ordinate axis; b is center point of Y-ordinate axis
+ R is the radius of the circle
+ ωt is the current angle at a specific time
Linear motion, also known as rectilinear motion, occurs when a particle's movement is described using just one coordinate axis and time Common examples of linear motion include a parade of soldiers marching in formation and a train traveling along a straight track.
In this project, there are two types of rectilinear motion such as uniformly accelerated motion and uniformly decelerated motion In order to understand those definition, following to below:
+ Uniformly Accelerated motion: When a body moves along a straight line and its velocity increases by equal amounts in equal interval of time then the motion is called uniformly accelerated motion
+ Uniformly Decelerated motion: When a body moves along a straight line and its velocity decreases by equal amounts in equal interval of time then the motion is called uniformly accelerated motion
Hence, there would be some formulas used for calculation:
The equation for the uniformly variable rectilinear motion of time-ordinate:
Equation for the time-velocity: v v 0 at (6)
Equation for acceleration and velocity:
Uniformly variable circular motion is a motion whose orbit is a circle and the angular speed of an object increases or decreases uniformly with time
There are some formulas used for calculation:
Equation for the uniformly variable circular motion of time-ordinate: φ = ωot + 1
Equation for the time-velocity: ω = ωo + γ.t (9)
Equation for acceleration and velocity: ω 2 - ωo 2 = 2γ.φ (10)
4.4.3.1 Calculations for the harmonic oscillation:
Main purpose: to determine the maximum speed for synchronization and verify the satisfied condition of the co-ordinates of harmonic oscillation
From the actual data collection, those data would be shown as below:
+ Center point I (a,b), where a equals to 268 955,4 μm and b equals to 39 722,1 μm + The circle radius R would be equal to approximately 41 680 μm
+ The angle value of φ would be (+) 20°
Institute those data into (1), (2), (3) and (4) equations, we get that:
Then, by instituting the different angle at specific time, we get the graph of both the harmonic oscillation and harmonic velocity as below:
* Note: The detail calculated data would be shown in appendix
The graph of calculated the harmonic oscillation:
The graphs illustrating the X and Y ordinates during one revolution of harmonic oscillation demonstrate that the maximum values on both axes align with the mechanical system's upper and lower stroke limits Specifically, the stroke limit for the X-axis ranges from -45,000 μm to 365,000 μm, while the Y-axis stroke limit spans from -85,000 μm to 87,000 μm.
By following to given formula (1’) and (2’), when cos(ωt + 20°) and sin(ω t + 20°) are equal to -1 or 1, it is obvious that the range of X-axis could be from 227 315, 4μm to
310 675,4μm and the Y-axis stroke could be from -1 957,9μm to 81 402,1μm Hence, the
100 calculated harmonic oscillation data are satisfied with the condition for use After that, those data would be used for testing with actual experiment for selection
Figure 4.46: The line chart illustrate the position of Axis X and Y at one revolution
The graph calculated the harmonic velocity at four different speed values:
The graphs illustrate that as speed values increase, the curves only show a change in magnitude for each revolution The primary goal of calculating harmonic velocity at various speeds is to determine the maximum speed during synchronization Notably, when the rotary table operates at 43,200 deg/min (120 rpm), the X-axis speed peaks at 3142 rpm (ωt = 250°) or -3142 rpm (ωt = 70°), while the Y-axis reaches a maximum of 2618.8 rpm (ωt = 340°) or -2618.8 rpm (ωt = 160°).
Position of X-Axis at one revolution
Position of Y-Axis at one revolution
The maximum operational speed of the current used motor is 3000 rpm, which primarily affects the X-axis speed when running the rotary table at a high speed of 120 rpm.
To address the issue, it is clear that the values in question represent instantaneous speed, which only occurs briefly at ωt = 250° and ωt = 70°, preventing any overspeed situations Therefore, the maximum synchronous speed for a rotary table with two linear motions is set at 120 rpm.
Figure 4.47: The line chart illustrate the velocity of two axes X and Y
4.4.3.2 Calculations for uniformly variable rectilinear motion:
The primary objective is to calculate the duration from the completion of object picking to the moment the rotary table aligns with the linear lead screws Subsequently, the velocities of both the X and Y axes will be determined to reach this alignment within the specified timeframe Finally, it is crucial to compare the calculated velocities with the system's allowable velocity to ensure optimal performance.
ꙍ000 deg/min ꙍ000 deg/min ꙍ(800 deg/min ꙍC200 deg/min
ꙍ000 deg/min ꙍ000 deg/min ꙍ(800 deg/min ꙍC200 deg/min
(deg/min) (deg) (min) (rpm) (rpm) (μm) (rpm) (μm) (rpm)
Let (*) be the unknown factor which should be calculated
At the beginning, there would be some initial common equations from the current value on given table as following:
The synchronous attaching period calculation: t sync = 𝛟(𝑑𝑒𝑔)
From the (5), (6) equations and initial speed of both axes is zero, then we get:
Instituting (5’) equation into (6’) equation, then we get that:
In this part, the first object would be the example for calculation After that, the other would follow to that method
Calculation for the first object:
Dealing with the speed of 10 000 deg/min, the time period to the table rotating with
495 degrees could be calculated as: t sync = 𝛟(𝑑𝑒𝑔)
10 000 = 0,0495 (𝑚𝑖𝑛) The last velocity of X-axis would be:
The last velocity of Y-axis would be:
Following to that calculation method, then we get the results as below:
(deg/min) (deg) (min) (rpm) (rpm) (μm) (rpm) (μm) (rpm)
Table 4.1: The calculation of the acceleration of four objects
From those calculated data, it is obvious that the accelerated speed of both axes are all in the allowable speed which should be less than 3000 rpm
The primary objective of this study is to calculate the duration from when two linear lead screws with a rotary table cease operation to the moment they are ready to pick the next object This involves determining the initial velocities of both the X and Y axes required to reach the next position within the specified time frame Ultimately, it is crucial to compare the calculated velocities against the system's allowable velocity to ensure optimal performance.
(deg/min) (deg) (min) (rpm) (rpm) (μm) (rpm) (μm) (rpm)
Let (*) be the unknown factor which should be calculated
At the beginning, there would be some initial common equations from the current value on given table as following:
The synchronous attaching period calculation: t sync = 𝛟(𝑑𝑒𝑔)
From the (5), (6) equations and initial speed of both axes is zero, then we get:
Instituting (5’’) equation into (6’’) equation, then we get that:
In this part, the first object would be the example for calculation After that, the other would follow to that method
Calculation for the first object:
Dealing with the speed of 10 000 deg/min, the time period to the table rotating with
495 degrees could be calculated as: t sync = 𝛟(𝑑𝑒𝑔)
The last velocity of X-axis would be:
The last velocity of Y-axis would be:
Following to that calculation method, then we get the results as below:
(deg/min) (deg) (min) (rpm) (rpm) (μm) (rpm) (μm) (rpm)
Table 4.2: The calculation of the deceleration of four objects
HMI Design
Figure 4.52: Initial interface at system startup
The screen displays information about the names, student numbers of our team members and instructors Besides, that is the hardware image that our team has completed the design
At the bottom of the screen is the name of the screen that we are communicating with and two buttons to switch the screen page
The monitoring screen presents the measurements of movement across three axes within the system, alongside the positions of objects located on the pole and turntable, as well as an indicator light that reflects the operational status.
In the frame “CURRENT FEED VALUE” displays the addresses of the axes that are standing outside the actual waiting
To identify faults or issues within the system, the "ERROR" frame will display error data related to the motor axes, enabling the detection of problems that require attention.
The control panel located in the right corner features buttons for system operation, automatic object dropping, and displaying warning alerts Pressing the "AUTO ON" button initiates automatic operation, transporting objects from the cylinder to the rotating round table In contrast, the "AUTO OFF" button halts the system in case of unexpected events.
Besides, there are screen switching buttons in the “NAVIGATION” frame
+ The yellow button “ALARM SCREEN” switches the display of the system problem warning screen
+ LOG OUT: is the button to log out the account you are accessing and return to the original main screen
The buttons in the “Test Operation” frame are used to move the independent axes to the desired locations:
+ JOG is a button that controls the axis to move when held down in the negative or positive direction
+ ABS is the button that controls the axis to move to the position set in “SETTING POSITION”
+ INC is the button that controls the axis to move one more segment set in
In the "Position Control Setting" frame control the axes simultaneously:
+ “HOME ALL” is the button that controls the axes to move to the position where the DOG sensor returns the values to 0
+ “XY LINEAR” is the button that controls the X and Y axes to move to the position where the program has been written
+ “SETTING POSITION” is a screen switch to set parameters to control axes according to needs
In the frame “MAGNET CONTROL” are the buttons to control the magnet
Upon system startup, activating the address is essential for controlling the servo motor, allowing it to enter a standby state, which is managed by the "Operation Adjustment" box.
Synchronous control is managed via the buttons in the “Synchronous Operating” frame When synchronous mode is activated, commands for the X, Y, and Z axes are disabled, and control is instead directed through the turntable axis for operation.
Finally, the yellow buttons at the “RESET ERROR” frame will reset the system error when the problems have been fixed
The screen allows users to configure JOG speed parameters, set addresses, and adjust the operating speed of the motor axes To navigate back to the control screen, simply click the “BACK” arrow located at the bottom of the interface.
The system's screen displays operational errors, providing detailed descriptions to help the operator identify and resolve issues Additionally, it tracks the frequency of each error, allowing for an assessment of the system's potential risks.
CONCLUTION AND THESIS DEVELOPMENT ORIENTATIONS
Result
Successfully built a 4-axis synchronous control system according to the set requirements
Separate control of main motor circular axis and X, Y, Z axes
The system is stable during operation
Motor runs precisely at high speed
Design control interface for automatic product picking system using GX Work2,
MT Developer 2, GT-Designer 3 software
Design the right part of the control screen and display warnings for the system
Conclusion
After conducting extensive research and refining the model for designing a high-speed control system to synchronize the rotary table with the linear motion lead screw, the student group has identified both the advantages and disadvantages of their topic.
The model can control multiple AC Servo motors at the same time
The system can run in many modes, the value can be changed to suit different requirements
The system is still limited to complex shapes
The model is small, so the scope of operation is limited
Cannot run stably and accurately when sucking too heavy objects
The system operation is only to pick and place the objects without any recognization such as vision or barcode reading
The ability of synchronous axes to follow a moving object on a circular trajectory traveling only on one trajectory of one diameter
Development orientations
Can combine other systems to work simultaneously
Adjust the pick-and-drop operation cycle to suit your requirements
The magnet device can be replaced with a robot hand for more flexible operation
The space of the axes can be expanded to operate other functions within the allowed area
It is possible to rotate the motor in reverse or for the shaft to pick up and drop the object from the turntable to pillar
[1] GENERAL-PURPOSE AC SERVO “SERVO MOTOR INSTRUCTION MANUAL (Vol.2)
[2] GENERAL-PURPOSE AC SERVO “SSCNET III INTERFACE / MODEL MR-J3- _B / SERVO AMPLIFIER INSTRUCTION MANUAL”
[3] “I/O Module Type Building Block User's Manual”
[4] “MOTION CONTROLLER Q-Series (Q173DSCPU/Q172DSCPU/Q173DSCPU(- S1)/Q172DSCPU(-S1)) User Manual“
[5] “Q173DSCPU/Q172DSCPU Motion Controller (SV22) Programming Manual (Advanced Synchronous Control)”
[6] “Q173DSCPU/Q172DSCPU Motion Controller (SV13/SV22) Programming Manual (REAL MODE)”
[7] “Q173DSCPU/Q172DSCPU Motion Controller (SV13/SV22) Programming Manual (Motion SFC)”
[8] “Mitsubishi Programmable Controller Training Manual Q Maintenance (for GX Works2)
[9] “MELSEC-Q/L Structured Programming Manual (Common Instructions)”
[10] “Motion Controller School Textbook (Advanced Synchronous Control Edition) Windows PC Compatible MT Works2”
[11] Website: “https://ocw.metu.edu.tr/pluginfile.php/6886/mod_resource/content/1/ch8/ 8- 3.htm” Author: Arthur Hays Sulzberger
[12] Website: “https://www.youtube.com/watch?v=HdtyczafhI4&t=1s” Name’s video:
“Disk Tracking Machine - Motion control made by Schneider Electric”
Calculated speed of two X and Y axes:
ꙍ000 deg/min ꙍ000 deg/min ꙍ(800 deg/min ꙍC200 deg/min
The calculated information and actual data of two axis X and Y running:
Angle Calculation Practical Absolute error (=