Position Control of a Two-Link Robotic Manipulator with Sliding-Mode Techniques

• Main Authors: Chien-Wei Chiu, 邱建瑋
• Other Authors: Yu-Sheng Lu
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/19912828225116547226

碩士 === 國立雲林科技大學 === 機械工程系碩士班 === 94 === Robotic manipulators are articulated mechanisms with highly nonlinear and coupled dynamics. Arc and spot welding, spray painting, milling and drilling etc. are some of its applications. For robust trajectory tracking, those proposed schemes are implemented on a homemade two-link robotic manipulator with various payloads and disturbances. In the experimental setup, we utilized TI’s TMS320C6711 DSP with an FPGA as our control kernel. Moreover, we establish an interface to two shaft encoders, ADCs and DACs using hardware description language (VHDL). For implementing control laws, we applied the C/C++ language as a tool. In conventional sliding mode control, system responses are sensitive to system perturbations during the reaching phase. In order to improve performance robustness, the global sliding-mode control (GSMC) scheme was proposed, that reveals the existence conditions of a global sliding mode, and ensures that the state of the system is constrained on the sliding regime throughout an entire response. However, there are various sliding dynamics which satisfied the existence conditions of a global sliding mode. So, how to design sliding dynamics which yields excellent system performance is an important issue. Therefore, this thesis proposed sliding dynamics, Generalized GSMC, Finite-Time Target-Reaching GSMC and Lag GSMC. To avoid the chattering that caused by GSMC, and to compensate for disturbance of the system, integral sliding-mode disturbance observer (I-SDOB) and internal model principle-based sliding-mode disturbance observer (IMP-Based SDOB) are proposed. Moreover, a mechanism of switching gain adaptation is proposed to properly adjust the switching gain.