scholarly journals Medical Grabbing Servo System with Friction Compensation Based on the Differential Evolution Algorithm

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Yeming Zhang ◽  
Kaimin Li ◽  
Meng Xu ◽  
Junlei Liu ◽  
Hongwei Yue
Keyword(s):  
Control System ◽  
Differential Evolution ◽  
Position Control ◽  
Differential Evolution Algorithm ◽  
Servo System ◽  
Physical Structure ◽  
Pneumatic Cylinder ◽  
Friction Compensation ◽  
Evolution Algorithm ◽  
Position Control System

AbstractThis paper introduces a pneumatic finger cylinder servo control system for medical grabbing. First, according to the physical structure of the proportional directional valve and the pneumatic cylinder, the state equation of the gas in the servo system was obtained. The Stribeck friction compensation model of a pneumatic finger cylinder controlled by a proportional valve was established and the experimental platform built. To allow the system output to better track the change in the input signal, the flow-gain compensation method was adopted. On this basis, a friction compensation control strategy based on a differential evolution algorithm was proposed and applied to the position control system of a pneumatic finger cylinder. Finally, the strategy was compared with the traditional proportional derivative (PD) strategy and that with friction compensation. The experimental results showed that the position accuracy of the finger cylinder position control system can be improved by using the friction compensation strategy based on the differential evolution algorithm to optimize the PD parameters.

Impedance Control of a Pneumatic Servo System with Adaptive Control Method

1991 ◽  
Vol 3 (6) ◽  
pp. 463-469 ◽  
Author(s):  
Toshiro Noritsugu ◽  
◽  
Tsutomu Wada ◽  
Toshiaki Asanoma ◽  
◽  
...  
Keyword(s):  
Adaptive Control ◽  
Control System ◽  
Position Control ◽  
Control Method ◽  
Reference Model ◽  
Impedance Control ◽  
Servo System ◽  
Operating Conditions ◽  
Pneumatic Cylinder ◽  
Pneumatic Servo System

One of the typical features of a pneumatic servo is a relatively high compliance due to air compressibility. This feature may be useful for constrained tasks such as deburring, polishing, and assisting humans, in which the relationship between position and force is important. If this relationship of a pneumatic servo becomes actively controllable, it can be effectively applied to these tasks. In order to control this relationship, an impedance control concept has recently been proposed. The impedance of the overall control system depends not only on the manipulator but also on the manipulated object of which the characteristics are usually unknown. Therefore, to attain the desired impedance over extensive operating conditions, an adaptive control strategy is required. This paper proposes an impedance control method of a pneumatic servo, using a position based approach, where an adaptive position control system is constructed inside the force feedback loop. The proposed method is applied to an experimental pneumatic servo system comprised of a pneumatic cylinder, electro-pneumatic proportional control valves, and a spring object. From the experiments, the following has been verified: 1) both static stiffness and dynamic impedance of the pneumatic servo system can be independently regulated by setting a desired reference model; 2) the impedance can be held constant with changes in system parameter such as object stiffness; and 3) the instability problem for the low stiffness setting can be overcome by setting high damping in the reference model. The proposed impedance control method may prove to be effective for both improving a pneumatic servo and developing its new applications.

Adaptive differential evolution algorithm identification of photoelectric tracking servo system

2016 ◽  
Vol 45 (7) ◽  
pp. 0731002 ◽  
Author(s):  
程 龙 Cheng Long ◽  
陈 娟 Chen Juan ◽  
陈茂胜 Chen Maosheng ◽  
徐 婧 Xu Jing ◽  
王卫兵 Wang Weibing ◽  
...  
Keyword(s):  
Differential Evolution ◽  
Differential Evolution Algorithm ◽  
Servo System ◽  
Adaptive Differential Evolution ◽  
Evolution Algorithm
Sign in / Sign up

Export Citation Format

Share Document