Modelling and control of a robotic manipulator subject to base disturbances

This thesis presents the modelling and control of a high gear ratio robotic manipulator mounted on a heavier moving base which is subject to base disturbances. The manipulator motion is assumed not to affect the base motion. The problem of a robotic manipulator on a non-inertial base can be applied to operation on sea vessels or all-terrain vehicles, where the base motion is unknown and cannot be used as a feed-forward signal to the model. A dynamic model is derived for the PA10-6CE manipulator with the assumption of a fixed base and the model terms are analysed numerically when comparing the simulation and experimental results. Based on the obtained results a set of model based controllers is compared to a basic proportional and derivative type controller to evaluate the trajectory tracking gains and trade-offs. The dynamic model is extended to the case of a manipulator on a moving base and numerical comparisons of simulation and experimental results are used to verify the model validity and the significance of the various model terms. From the results of this study a set of model based controllers is obtained. A novel adaptive scheme is then proposed for compensation of an unknown and varying gravity acceleration vector acting on the manipulator base. Controllers based on using an additional sensor output are compared with static and adaptive gravity controllers and the latter proved to be superior in terms of trajectory tracking performance

Modelling and control of a robotic manipulator subject to base disturbances

This thesis presents the modelling and control of a high gear ratio robotic manipulator mounted on a heavier moving base which is subject to base disturbances. The manipulator motion is assumed not to affect the base motion. The problem of a robotic manipulator on a non-inertial base can be applied to operation on sea vessels or all-terrain vehicles, where the base motion is unknown and cannot be used as a feed-forward signal to the model. A dynamic model is derived for the PA10-6CE manipulator with the assumption of a fixed base and the model terms are analysed numerically when comparing the simulation and experimental results. Based on the obtained results a set of model based controllers is compared to a basic proportional and derivative type controller to evaluate the trajectory tracking gains and trade-offs. The dynamic model is extended to the case of a manipulator on a moving base and numerical comparisons of simulation and experimental results are used to verify the model validity and the significance of the various model terms. From the results of this study a set of model based controllers is obtained. A novel adaptive scheme is then proposed for compensation of an unknown and varying gravity acceleration vector acting on the manipulator base. Controllers based on using an additional sensor output are compared with static and adaptive gravity controllers and the latter proved to be superior in terms of trajectory tracking performance.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Internet remote control interface for a multipurpose robotic arm

This paper presents an Internet remote control interface for a MITSUBISHI PA10-6CE manipulator established for the purpose of the ROBOT museum exhibition during spring and summer 2004. The robotic manipulator is a part of the Intelligent Robotic Systems Laboratory at Heriot ? Watt University, which has been established to work on dynamic and kinematic aspects of manipulator control in the presence of environmental disturbances. The laboratory has been enriched by a simple vision system consisting of three web-cameras to broadcast the live images of the robots over the Internet. The Interface comprises of the TCP/IP server providing command parsing and execution using the open controller architecture of the manipulator and a client Java applet web-site providing a simple robot control interface