Force control of redundant robots in unstructured environment

2002 ◽  
Vol 49 (1) ◽  
pp. 233-240 ◽  
Author(s):  
B. Nemec ◽  
L. Zlajpah
Author(s):  
Bojan Nemec ◽  
◽  
Leon Zlajpah Institute Jozef Stefan

The paper describes the implementation of the force control for redundant robots in an unstructured environment. We assume that the obstacles are not known in advance. Hence, the robot arm has to be compliant with the environment while tracking the desired position and force at the end effector. Using the minimal null space approach the appropriate impedance controller, which decouples the end effector and the null space spaces was derived. The control algorithm enables the selection of dynamic characteristics in both subspaces independently.The proposed method was verified with the simulation and with experiments on a 4 D.O.F planar redundant robot.


1999 ◽  
Vol 27 (3) ◽  
pp. 111-127 ◽  
Author(s):  
Krzysztof P. Jankowski ◽  
Hoda A. ElMaraghy

1997 ◽  
Vol 30 (20) ◽  
pp. 209-214
Author(s):  
Bojan Nemec

2008 ◽  
Vol 35 (S 01) ◽  
Author(s):  
Y Li ◽  
J Randerath ◽  
G Goldenberg ◽  
J Hermsdörfer

2005 ◽  
Vol 32 (S 4) ◽  
Author(s):  
F Kirsten ◽  
S Bohlen ◽  
J Sommer ◽  
T Merl ◽  
P Saemann ◽  
...  

Author(s):  
K. Shibazaki ◽  
H. Nozaki

In this study, in order to improve steering stability during turning, we devised an inner and outer wheel driving force control system that is based on the steering angle and steering angular velocity, and verified its effectiveness via running tests. In the driving force control system based on steering angle, the inner wheel driving force is weakened in proportion to the steering angle during a turn, and the difference in driving force is applied to the inner and outer wheels by strengthening the outer wheel driving force. In the driving force control (based on steering angular velocity), the value obtained by multiplying the driving force constant and the steering angular velocity,  that differentiates the driver steering input during turning output as the driving force of the inner and outer wheels. By controlling the driving force of the inner and outer wheels, it reduces the maximum steering angle by 40 deg and it became possible to improve the cornering marginal performance and improve the steering stability at the J-turn. In the pylon slalom it reduces the maximum steering angle by 45 deg and it became possible to improve the responsiveness of the vehicle. Control by steering angle is effective during steady turning, while control by steering angular velocity is effective during sharp turning. The inner and outer wheel driving force control are expected to further improve steering stability.


Sign in / Sign up

Export Citation Format

Share Document