Final state control based on high-speed positioning control considering acceleration and speed limits for industrial robot

AbstractDuring the various stages of shock loading, many transient modes of deformation can activate and deactivate to affect the final state of a material. In order to fundamentally understand and optimize a shock response, researchers seek the ability to probe these modes in real-time and measure the microstructural evolutions with nanoscale resolution. Neither post-mortem analysis on recovered samples nor continuum-based methods during shock testing meet both requirements. High-speed diffraction offers a solution, but the interpretation of diffractograms suffers numerous debates and uncertainties. By atomistically simulating the shock, X-ray diffraction, and electron diffraction of three representative BCC and FCC metallic systems, we systematically isolated the characteristic fingerprints of salient deformation modes, such as dislocation slip (stacking faults), deformation twinning, and phase transformation as observed in experimental diffractograms. This study demonstrates how to use simulated diffractograms to connect the contributions from concurrent deformation modes to the evolutions of both 1D line profiles and 2D patterns for diffractograms from single crystals. Harnessing these fingerprints alongside information on local pressures and plasticity contributions facilitate the interpretation of shock experiments with cutting-edge resolution in both space and time.

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Long-Stroke Nanopositioning Stage Driven by Piezoelectric Motor

Journal of Sensors ◽

10.1155/2014/926314 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Yong Wang ◽

Fujun Sun ◽

Junhui Zhu ◽

Ming Pang ◽

Changhai Ru

Keyword(s):

High Speed ◽

Control Method ◽

Laser Vibrometer ◽

Piezoelectric Motor ◽

Backward Error ◽

Positioning Control ◽

Ac Drive ◽

Variable Friction ◽

Long Stroke ◽

Speed Characteristic

This paper reported a biaxial nanopositioning stage single-driven by piezoelectric motor. The employed piezoelectric motor can perform two different driving modes, namely, AC drive mode to drive in long-stroke and at high-speed and DC scanning mode with the high-resolution of several nanometers, which satisfies the requirements of both long-stroke and nanoresolution. To compensate for the effects of the variable friction force and some unpredictable disturbances, a novel backward error compensation (BEC) positioning control method integrated of the two driving modes and a double closed-loop PID controller system are proposed to obtain a high-accuracy positional motion. The experiment results demonstrate that the nanopositioning stage with large travel range of 300 mm × 300 mm has a fine speed characteristic and resolution is 5 nm. In the experiments of different travels up to 15 mm, calibrated by a commercial laser vibrometer, the positioning accuracy is proved within 55 nm inx-axis and 40 nm iny-axis with standard deviation less than 40 nm inx-axis and 30 nm iny-axis and the final position locking can be limited to 10 nm, meeting the requirements of micromanipulation technology.

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A Design Method of Robust Control System for Three-inertia Benchmark Problem Using Model Error Compensator and Frequency Shaped Final-state Control

Transactions of the Society of Instrument and Control Engineers ◽

10.9746/sicetr.50.861 ◽

2014 ◽

Vol 50 (12) ◽

pp. 861-868 ◽

Cited By ~ 4

Author(s):

Takumi FUJIOKA ◽

Hiroshi OKAJIMA ◽

Nobutomo MATSUNAGA

Keyword(s):

Control System ◽

Robust Control ◽

Design Method ◽

Model Error ◽

State Control ◽

Benchmark Problem ◽

Final State ◽

Robust Control System

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Final-State Control Using a Time-Symmetric Polynomial Input

IEEE Transactions on Control Systems Technology ◽

10.1109/tcst.2011.2178024 ◽

2012 ◽

Vol 20 (2) ◽

pp. 395-401 ◽

Cited By ~ 4

Author(s):

Mitsuo Hirata ◽

Fujimaru Ueno

Keyword(s):

Symmetric Polynomial ◽

State Control ◽

Final State

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Current Control for SPMSM in Field-Weakening Region Based on Final-State Control

Electrical Engineering in Japan ◽

10.1002/eej.22491 ◽

2014 ◽

Vol 188 (2) ◽

pp. 68-77

Author(s):

Takayuki Miyajima ◽

Hiroshi Fujimoto ◽

Masami Fujitsuna

Keyword(s):

Current Control ◽

State Control ◽

Final State ◽

Field Weakening

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EFFECT OF SERVO SYSTEMS ON THE CONTOURING ERRORS IN INDUSTRIAL ROBOTS

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2012-0006 ◽

2012 ◽

Vol 36 (1) ◽

pp. 83-96 ◽

Cited By ~ 10

Author(s):

Mohamed Slamani ◽

Albert Nubiola ◽

Ilian A. Bonev

Keyword(s):

High Speed ◽

Industrial Robot ◽

Statistical Tests ◽

Measurement Instrument ◽

Servo System ◽

Industrial Robots ◽

Structural Vibration ◽

Tool Centre Point ◽

Prediction Capability ◽

Radius Size

Two important aspects of the performance of a servo system, tracking errors and contour errors, significantly affect the accuracy of industrial robots under high-speed motion. Careful tuning of the control parameters in a servo system is essential, if the risk of severe structural vibration and a large contouring error is to be avoided. In this paper, we present an overview of a method to diagnose contouring errors caused by the servo control system of an ABB IRB 1600 industrial robot by measuring the robot’s motion accuracy in a Cartesian circular shape using a double ballbar (DBB) measurement instrument. Tests were carried out at different TCP (tool centre-point) speed and trajectory radii to investigate the main sources of errors that affect circular contouring accuracy. Results show that radius size errors and out-of-roundness are significant. A simple experimental model based on statistical tests was also developed to represent and predict the radius size error. The model was evaluated by comparing its prediction capability in several experiments. An excellent error prediction capability was observed.

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