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Introduction 1.1Mechatronics definition Mechatronics is the combination of mechanical engineering , electronic engineering , computer engineering . Software engineering , Control engineering , and system design engineering in order to design , and manufacture useful products . Originally , mechatronics just included the combination between mechanics and electronics , hence the word is only combination between mechanics and electronics. Fig() 1.2 Mechatronics Applications: Machine vision Automation and robotics Servomechanics Sensing and control system Expert systems Industrial goods3 Microcontrollers PLC’s Medical mechatronics , medical imaging systems Structural dynamic systems Transportation and vehicular systems Mechatronics as the new language of the automobile Diagnostic , reliability and control system techniques 1.3 Control systems Interconnection of components forming system configuration which will provide a desired system response as time progresses . the key characteristic of control is to interfere , to influence : 1.3.1 Functions of a Control System: 1. Measurement: This is essentially an estimate or appraisal of the process being controlled by the system 2. Comparison: This is an examination of the likeness of the measured values and the desired values 3. Computation : This is a calculated judgment that indicates how much the measured value and the desired values differ and what action and how much should be taken. 4. Correction :This is ultimately the materilisation of the order for the adjustment . 1.3.2 Hardware of a Control System : Examining the automatic control system, it is found that it contains the following hardware Sensor : a piece of equipment to measure system variables. It serves as the signal source in automatic control Controller : a piece of equipment to perform the functions of comparison and computation Control Element : a piece of equipment to perform the control action or to exert direct influence on the process 1.3.3 Software of a Control System: Associated with a control system are a number of different types of variables.4 First we have the Controlled Variable. This is the basic process value being regulated by the system. It is the one variable that we are specially interested in the outlet water temperature in the example above. In feedback control the controlled variable is usually the measured variable. An important concept related to the controlled variable is the Setpoint. This is the predetermined desired value for the controlled variable. The objective of the control system is to regulate the controlled variable at its setpoint. To achieve the control objective there must be one or more variables we can alter or adjust. These are called the Manipulated VariablesConclusively, in the control system we adjust the manipulated variable to maintain the controlled variable at its setpoint. This meets the requirement of keeping the stability of the process and suppressing the influence of disturbances. 1.4 Motivation to our project: The main factor at dosing of components and micro components, which defines the quality of the dosing process, is the exactness of measurement the weight by the electronic machines Dosing of materials from set of main silos to weighing containers placed in various location of a plant; bulk and fine dosing; automation of liquid dosing processes; possibility of applying a system algorithm for dosing random liquid substances dosed in a forced way. This project is suitable for many industrial applications in which costeffective weight measurements have to be performed with little engineering overhead. This set is particularly suitable if additionally automated logging functions are required in the framework of the measurement5 1.5 Aim of the Project: 1 Studying the system and estimating its problems . 2 Studying the performance of the system . 3Studying the dosing and mixing control system using PLC HMI 4Applying simulation programs on the system for studying the positives negatives of design 5Redesign and rebuild the system based on the mechatronics application.6 Chapter Two Project description7 Introduction In this chapter we will talk about our project objectives ,components and how to reach to our objective by using these components 2.1 Project description 2.1 System description Fig(21)8 2.2 system description: The system consists of two stages (mixing process and dosing process) The first stage is mixing process which three liquids are poured from three different tanks in specific percentages and specific weight by the operator using HMI touch screen into mixing tank . Then the mixing process takes a place for a specific period of time At the second stage : The conveyor runs under the mixer vertically with the mixer solenoid valve and the proximity sensor works as a detector for the empty product container under the mixer solenoid valve to dose it. For accuracy assurance of the process the container has weighted within the dosing process by loading it on a load cell lifted by double acting cylinder which is controlled by pneumatic solenoid valve and the dosing starts until getting to the required value of the product which the operator was entered by HMI touch screen. The load cell works as a weight sensor which gives a feedback of the current product weight. Then , by getting to the required weight the mixer solenoid valve is closed the pneumatic solenoid valve brings the load cell down and the dosed container on the conveyor which moves it to make the system ready for the next dosing process . The other function of the proximity sensor is to count the number of the products 2.3 Power supply PS 307; 5 A power supply module: 2.2.1 Properties of the PS 307; 5 A power supply module: ● Output current 5 A ● Output voltage 24 VDC; short circuitproof, open circuitproof ● Connection to singlephase AC mains (rated input voltage 120230 VAC, 5060 Hz) ● Safety isolation to EN 60 950 ● May be used as load power supply
Chapter One Introduction Introduction 1.1Mechatronics definition Mechatronics is the combination of mechanical engineering , electronic engineering , computer engineering Software engineering , Control engineering , and system design engineering in order to design , and manufacture useful products Originally , mechatronics just included the combination between mechanics and electronics , hence the word is only combination between mechanics and electronics Fig() 1.2 Mechatronics Applications: Machine vision Automation and robotics Servo-mechanics Sensing and control system Expert systems Industrial goods Microcontrollers / PLC’s Medical mechatronics , medical imaging systems Structural dynamic systems Transportation and vehicular systems Mechatronics as the new language of the automobile Diagnostic , reliability and control system techniques 1.3 Control systems Interconnection of components forming system configuration which will provide a desired system response as time progresses the key characteristic of control is to interfere , to influence : 1.3.1 Functions of a Control System: Measurement: This is essentially an estimate or appraisal of the process being controlled by the system Comparison: This is an examination of the likeness of the measured values and the desired values Computation : This is a calculated judgment that indicates how much the measured value and the desired values differ and what action and how much should be taken Correction :This is ultimately the materilisation of the order for the adjustment 1.3.2 Hardware of a Control System : Examining the automatic control system, it is found that it contains the following hardware Sensor : a piece of equipment to measure system variables It serves as the signal source in automatic control Controller : a piece of equipment to perform the functions of comparison and computation Control Element : a piece of equipment to perform the control action or to exert direct influence on the process 1.3.3 Software of a Control System: Associated with a control system are a number of different types of variables First we have the Controlled Variable This is the basic process value being regulated by the system It is the one variable that we are specially interested in - the outlet water temperature in the example above In feedback control the controlled variable is usually the measured variable An important concept related to the controlled variable is the Setpoint This is the predetermined desired value for the controlled variable The objective of the control system is to regulate the controlled variable at its setpoint To achieve the control objective there must be one or more variables we can alter or adjust These are called the Manipulated VariablesConclusively, in the control system we adjust the manipulated variable to maintain the controlled variable at its setpoint This meets the requirement of keeping the stability of the process and suppressing the influence of disturbances 1.4 Motivation to our project: The main factor at dosing of components and micro components, which defines the quality of the dosing process, is the exactness of measurement the weight by the electronic machines Dosing of materials from set of main silos to weighing containers placed in various location of a plant; bulk and fine dosing; automation of liquid dosing processes; possibility of applying a system algorithm for dosing random liquid substances dosed in a forced way This project is suitable for many industrial applications in which costeffective weight measurements have to be performed with little engineering overhead This set is particularly suitable if additionally automated logging functions are required in the framework of the measurement 1.5 Aim of the Project: 1- Studying the system and estimating its problems 2- Studying the performance of the system 3-Studying the dosing and mixing control system using PLC & HMI 4-Applying simulation programs on the system for studying the positives & negatives of design 5-Redesign and rebuild the system based on the mechatronics application Chapter Two Project description Introduction In this chapter we will talk about our project objectives ,components and how to reach to our objective by using these components 2.1 Project description 2.1 System description Fig(2-1) 2.2 system description: The system consists of two stages (mixing process and dosing process) The first stage is mixing process which three liquids are poured from three different tanks in specific percentages and specific weight by the operator using HMI touch screen into mixing tank Then the mixing process takes a place for a specific period of time At the second stage : The conveyor runs under the mixer vertically with the mixer solenoid valve and the proximity sensor works as a detector for the empty product container under the mixer solenoid valve to dose it For accuracy assurance of the process the container has weighted within the dosing process by loading it on a load cell lifted by double acting cylinder which is controlled by pneumatic solenoid valve and the dosing starts until getting to the required value of the product which the operator was entered by HMI touch screen The load cell works as a weight sensor which gives a feedback of the current product weight Then , by getting to the required weight the mixer solenoid valve is closed the pneumatic solenoid valve brings the load cell down and the dosed container on the conveyor which moves it to make the system ready for the next dosing process The other function of the proximity sensor is to count the number of the products 2.3 Power supply [PS 307; A power supply module]: 2.2.1 Properties of the PS 307; A power supply module: ● Output current A ● Output voltage 24 VDC; short circuit-proof, open circuit-proof ● Connection to singlephase AC mains (rated input voltage 120/230 VAC, 50/60 Hz) ● Safety isolation to EN 60 950 ● May be used as load power supply Fig(2-2) 2.3.1 Wiring diagram of PS 307; A Fig(2-3) 2.4 The controller The main controller of the system is the plc type S7314C-2DP Technical specifications of CPU 314C-2DP 01 YES TURN MOTOR ON CLOSE PENUMATIC VALVE SOLENOID MIXER OFF NO NO OF PRODUCT = REQUIRED NO END 2ND STAGE 88 Reference: SIWAREX_FTA-en_V01 PC_Adapter_USB_e s7300_cpu_31xc_and_cpu_31x_manual_en-US_en-US hmi_wincc_v6_2_getting_started_en Quality Assurance graduation project 2010 Multi Component Dosing by Weighing Control graduation project 2011 Constant water level in reservoir graduation project 2011 http://support.automation.siemens.com https://www.automation.siemens.com/WW/forum/guests/PostS how.aspx?PageIndex=1&PostID=110356&Language=en 89 Appendix 91 APPENDIX A PLC SPECIFICATIONS 90 92 93 APPENDIX B HMI TECHNICAL DATA 94 Display 5.7 inch STN display , blue mode levels Resolution 320 x 240 or 240 x 320 pixel Control elements Touch screen resistive analog User memory 256 KB Interfaces x RS485 Installation cutout 198 x 142 mm (W x H) Front panel 212 x 156 mm (W x H) Depth 44 mm Configuration software Wincc flexible compact 95 APPENDIX C LOAD CELL GETTING STARTED 96 SIWATOOL FTA Types of siwarex tool: SIWAREX FTA SIWAREX U SIWAREX CS SIWAREXFTC Function The primary task of the SIWAREX FTA consists of the precise measurement of the current weight values in up to three measurement ranges and the exact control of the weighing procedure The control of the weighing procedure is completely run from the weighing module as if in separately constructed weighing electronics The integration in SIMATIC enables the progress of the weighing procedure to be influenced directly from the PLC program however This enables reasonable task 97 distribution: The extremely fast weighing functions are performed in the SIWAREX module, latching and signal linking is done in the PLC There are different automatic weighing procedures for which SIWAREX FTA can be configured optimally by defining the corresponding parameters Commissioning and Service with SIWATOOL FTA: For commissioning, there is a special program SIWATOOL FTA for Windows operating systems The program enables commissioning of the scale without having to understand automation technology During service procedures, you can analyse the processes in the scale and test them with the help of a PC Reading the diagnostics buffer from the SIWAREX FTA is very helpful in analysing events Besides complete access to all parameters, memory or print-outs of the weighing file, the program can create weighing curves as well SIWATOOL FTA can also be used for reading the contents of the calibratable records from the calibratable scale memory The following image shows the structure of the individual program windows 98 SIWAREX Connection areas for SIWAREX FTA The following connection areas are found on the front as Screw-in connector for 24 V power supply 40pin connector for load cell connection, digital input and output, RS 485 analog output, counter input 9pin (female) D-sub connector for RS 232 to PC or printer connection 99 The SIMATIC construction guidelines apply for connecting the 40 pin connector Flexible cables with a cross-section of 0.25 to 1.5 mm can be used Remove the insulation from the cable for mm and install wire end sleeves 011 Load cell connections : Sensors equipped with strain gauges and that meet the following conditions can be connected to the SIWAREX FTA Characteristic value mV/V Supply voltage of 10.2 V is permitted The connection is made to the 40 pin front connector The connection should be made using the cable described in chapter Accessories 010 Technical specifications of SIWAREX FTA 012 ... main factor at dosing of components and micro components, which defines the quality of the dosing process, is the exactness of measurement the weight by the electronic machines Dosing of materials... required in the framework of the measurement 1.5 Aim of the Project: 1- Studying the system and estimating its problems 2- Studying the performance of the system 3-Studying the dosing and mixing... closed the pneumatic solenoid valve brings the load cell down and the dosed container on the conveyor which moves it to make the system ready for the next dosing process The other function of the