so tay thiet ke nen mong

... láût: M giỉỵ > 1.5M láût - giu M : Mä men do lỉûc gáy ra so våïi tám quay cọ xu hỉåïng giỉỵ láût. - giu M : Mä men do lỉûc gáy ra so våïi mẹp mọng cọ xu hỉåïng gáy láût =×=×= 2 5,2 3,117 2

Ngày tải lên: 15/06/2015, 06:59

... MÓNG CỘT TRỤC A: Móng cột trục A móng biên có N; = 920KN;M" = 227KNm;Qu = 24KN Ta thấy nội lực nhỏ so với cột trục B nên ta chọn phương án móng nông thiên nhiên(là phương án rẻ nhất) 3.1, Xác đinh ... =0,026 (m) 026m < s h = 0,08m =>Thoả mãn điều kiên độ lún tuyêt đối , Ra=260000(kPa) n Độ lún lệch so với móng trục C: Khi tính toán độ bền ta phải dùng tổ hợp tải trọng bất lợi AS = ^Trọng = 0’062757 ... TRỤC A: Móng cột trục A là móng biên có N; = 920KN;M" = 227KNm;Qu = 24KN Ta thấy nội lực nhỏ so với cột trục B nên ta chọn phương án móng nông trên nền thiên nhiên(là phương án rẻ nhất)

Ngày tải lên: 07/01/2016, 17:40

... giỉỵa cạc âiv làng thãø chc thng ak : cảnh ca tiãút diãûn cäüt song song våïi mẹp ca làng thãø chc thng b : cảnh ca âạy âi song song våïi ak ho : chiãưu cao lm viãûc täøng cäüng ca âi Rp : sỉïc ... giỉỵa cạc âiv làng thãø chc thng ak : cảnh ca tiãút diãûn cäüt song song våïi mẹp ca làng thãø chc thng b : cảnh ca âạy âi song song våïi ak ho : chiãưu cao lm viãûc täøng cäüng ca âi Rp : sỉïc ... định lật Âiãưu kiãûn Mg > Ml Trong âọ: Mg -Mmä men ca cạc lỉûc so våïi tám cọ xu hỉåïng lm khäúi âáút bë trỉåüt Ml - Mä men ca cạc lỉûc so våïi tám cọ xu hỉåïng lm khäúi âáút bë trỉåüt Ml = Mtt +

Ngày tải lên: 08/05/2016, 22:38

... giỉỵa cạc âiv làng thãø chc thng ak : cảnh ca tiãút diãûn cäüt song song våïi mẹp ca làng thãø chc thng b : cảnh ca âạy âi song song våïi ak ho : chiãưu cao lm viãûc täøng cäüng ca âi Rp : sỉïc ... giỉỵa cạc âiv làng thãø chc thng ak : cảnh ca tiãút diãûn cäüt song song våïi mẹp ca làng thãø chc thng b : cảnh ca âạy âi song song våïi ak ho : chiãưu cao lm viãûc täøng cäüng ca âi Rp : sỉïc ... định lật Âiãưu kiãûn Mg > Ml Trong âọ: Mg -Mmä men ca cạc lỉûc so våïi tám cọ xu hỉåïng lm khäúi âáút bë trỉåüt Ml - Mä men ca cạc lỉûc so våïi tám cọ xu hỉåïng lm khäúi âáút bë trỉåüt Ml = Mtt +

Ngày tải lên: 08/05/2016, 22:38

... 19 were among the first who demonstrated the direct effect of flank wear on the cutting force, which motivated separation of the cutting force signal into two components, one associated with ... computational burden associated with obtaining the spectrum, which often precludes its on-line application. The alternative to single-sensor-based pattern classification is the multi-sensor approach using ... any samples of measurements to be taken at tool breakage. ART2, however, may not cope effectively with varying levels of noise associated with different sensors, and may classify multiples of

Ngày tải lên: 04/07/2014, 14:20

... visually detecting missing and broken tools and detecting chatter from the characteristic sound it generates. Unmanned monitoring algorithms utilize filtered sensor measure- ments that, along with ... monitored by sophisticated signal processing of sensor measurements that typically involve thresholding or artificial intelligence (AI) techniques. 1 For more information on sensors for process ... The spindle speed is varied about some nominal value, typically in a sinusoidal manner. Figures 6.10 and 6.11 demonstrate how varying the spindle speed sinusoidally with an amplitude of 50% of

Ngày tải lên: 04/07/2014, 14:20

... Springback 7.3 Machine Control Sensors 7.4 Machine Control: Force or Displacement? 7.5 Process Resolution Issues: Limits to Process Control Process Resolution Enhancement 7.6 Direct Shape ... process, but also the unloading. When looked at from a control system’s perspective, the material appears to be a static block with nonlinear behavior. This arises from a power law-like plastic region, ... Also, for three-dimensional forming problems, this tensile “bias” is also necessary to prevent in-plane buckling. From the above it is obvious that for sheet forming, springback is the main source

Ngày tải lên: 04/07/2014, 14:20

... and cool- ing rates. Among the most commonly used sensors are acoustic emission, audible sound (acoustic sensing), infrared/ultraviolet detectors, and optical (vision) sensors. A brief overview ... Wu and Richardson, 1989) by (8.2) where K 5 = K 0 mn, m = arc voltage — arc length characteristics slope, n = absolute value of the inverse of the power source characteristics ... second-order behavior: (8.12) Having outlined some of the basic models that constitute the basis for weld process control, we now discuss some of the more common sensor systems for monitoring process outputs.

Ngày tải lên: 04/07/2014, 14:20

... weight is also dependent on melt temperature and pressure, so a change in machine inputs may result in inaccurate packing times. After packing, the polymer melt is solidified but is too soft for ... Press. Melt Density Melt Temp. Solidified Layer Development Clamp Tonnage Solidified Layer Development Cycle Time Part Temp Part Strain Part Stress Ejection Stroke 0.02 Ejection Velocity 0.01 ... buildup of a solidified skin layer as well as the polymer’s complex non-Newtonian (shear dependent) rheological behavior. Based on these analyses, sophisticated simulations were soon introduced

Ngày tải lên: 04/07/2014, 14:20

... The Abbe Principle 10.4 Sources of Error and Error Budgets Sources of Errors • Determination and Reduction of Thermal Errors • Developing an Error Budget 10.5 Some Typical Methods of Measuring ... should be capable of having repeatability that is limited only by the resolution of its sensors. Figure 10.1 presents some of the factors affecting workpiece accuracy. 2 10.2 Basic Definitions ... Directions Of the six error terms associated with a given axis, some will affect the machine tool’s accuracy more than others. These error terms are associated with the sensitive directions

Ngày tải lên: 04/07/2014, 14:20

... because the sensor is located in the same strut as the actuator, the same influence vector b appears in the sensor Equation (11.5) and the equation of motion (11.3). If the force sensor is connected ... imaginary axis (or near if the structural damping is taken into account); on the other hand, G ( ω ) has a feedthrough component and some roll-off must be added to the compensator to achieve ... actuator and force sensor connected by a local controller with an integral force feedback (IFF). 11.2 Active Struts The first concept is the most natural; it consists of replacing some passive bars

Ngày tải lên: 04/07/2014, 14:20

... vibration. (a) (c) (b) Vibration isolator Vibration isolator source of vibration m absorber m a xa(t) F(t) = F 0 sin ( ω t) F(t) = F 0 sin ( ω t) c a ck m device source of vibration y(t) = Y ... ratio suppresses the resonance, it also compromises the isolation for the high-frequency region ( ). Similar to optimum vibration absorber, an optimal transfer function for the isolator can be obtained ... techniques. Some related practical developments ranging from vehicle suspensions to civil and aerospace structures are also reviewed. 12.1.1 Vibration Isolation vs. Vibration Absorption In

Ngày tải lên: 04/07/2014, 14:20

... wide-band vibration absorption, also the related optimization work and the stability analysis. 14.2 Delayed Resonator Dynamic Absorbers The delayed resonator (DR) dynamic absorber is an unconventional ... 14 Active Vibration Absorption and Delayed Feedback Tuning 14.1 Introduction 14.2 Delayed Resonator Dynamic Absorbers The Delayed Resonator Dynamic Absorber with Acceleration Feedback ... Feedback • Automatic Tuning Algorithm for the Delayed Resonator Absorber • The Centrifugal Delayed Resonator Torsional Vibration Absorber 14.3 Multiple Frequency ATVA and Its Stability

Ngày tải lên: 04/07/2014, 14:20

... Larson et al. (1998) to develop a high-stroke acoustic source over a wide frequency range. By switching between the open-circuit FIGURE 15.1 Schematics of some semi-active RSP damper/absorbers. ... absorber. That is, the absorber is tuned to the resonant frequency and sufficient damping (resistance) is added to give a flat frequency response around the resonant frequency. In the off-resonant ... With proper design of the shunt components (inductor, resistor, or capacitor), one can achieve the so- called electrical damper or electrical absorber effects. Soon after Hagood and von Flotow provided

Ngày tải lên: 04/07/2014, 14:20

... the dynamics of all components (structural components, controls, sensors, actuators, etc.). This requires new research. Control theory describes how the design of one component (the controller) ... all other components. However, in systems design, where more than one component remains to be designed, there is inadequate theory to suggest how the dynamics of two or more components should influence ... structure and control design appears in Skelton 1,2 and Grigoriadis et al. 3 Bendsoe and others 4-7 optimize structures by beginning with a solid brick and deleting finite elements

Ngày tải lên: 04/07/2014, 14:20

... define frame 0 is to take it coincident with frame 1 when q 1 = 0; this makes α 1 = 0 and and • A similar choice for frame n is to take X n along X n–1 when q n = 0; this makes • If joint i ... Although the axis can be arbitrary, the three components of r are constrained by the unit norm condition r T r = 1. (19.10) Also, it is clear that i.e., a rotation by about – ... of the quaternion of the opposite sign from the one associated with a rotation by about r , while the scalar part does not change. This solves the above nonuniqueness problem. The rotation

Ngày tải lên: 04/07/2014, 14:20

... the Dynamic Model 20.4 Some Applications of Computer-Aided Dynamics Dynamics and Robot Design • Dynamics in On-Line Control 20.5 Extension of Dynamic Modeling — Some Additional Dynamic ... expressed in the frame fixed to the link j . is the tensor of inertia calculated for the axes of the link-fixed frame. In a general case, the tensor has the form (20.15) However, if the frame axes ... However, if the frame axes are placed to coincide with the principal inertial axes, then the tensor takes the diagonal form (20.16) where is the inertial moment with respect to axis x j

Ngày tải lên: 04/07/2014, 14:20

... technology grows fast. Thus, some currently advanced constructive solutions might soon become obsolete. Hence, we decided to avoid presentation of specific constructive solutions and try to explain ... different hardware and software solutions. The problem of control is closely related to the driving characteristics of different types of actuators. Finally, constructive solutions of the robot’s ... of nonlinear multivariable systems like robots, stability of control, even force feedback, etc. It seems that robot industry did not believe the need for some exact theory. Experience in machine

Ngày tải lên: 04/07/2014, 14:20

... with respect to the source of force infor- mation (with or without direct interaction force sensing), and the allocation of force sensor (wrist, torque sensor in joints, force-sensing ... sensor in joints, force-sensing pedestal, force sensor at the contact surface, sensors at robot links, fingers, etc.). To avoid the problems associated with noncollocation between measurement of ... force control. The terminology used above represents, in some measure, a trade-off among different nomen- clatures used in the literature. Mason 1 designates the control concepts by specifying the

Ngày tải lên: 04/07/2014, 14:20

... is an ultrasonic transceiver/receiver sensor mounted on the unit end-point. The echoes are processed by an on-board computer to identify obstacles around the robot. A planner is a software module ... high-resolution CCD cameras and stereo-photogrammetry techniques; (2) surface mineral composition using two spectrometers, an oven soil heater, and a gas analyzer; and (3) regolith depths using sonar ... equipped with two high-resolution cameras with power zoom, auto iris, and focus capabilities mounted on a pan/tilt unit at the top of the octahedral frame. Ultrasonic ranging sensors were added for

Ngày tải lên: 04/07/2014, 14:20