Boom-type Roadheader Robot High Order Sliding Mode Control Research

Boom-type roadheader robot was a kind of advanced robot used for laneway excavation. The dissertation aim at the poor working environment and high level of risk problems, according to the quality of excavation operation requirements, to study a kind of boom-type roadheader robot control system, implement the unmanned operation under harsh environment such us laneway, underground and so on, and complete its scheduled operations automatically.The dissertation took boom-type roadheader as the target, according to excavation under the manual operation key technologies-cutting control and walking control, studied the cross-section forming and trajectory tracking control algorithm, and achieved the controller and the implemention of system. It had laid a theoretical foundation and provided an experimental platform in order to develop and produce a high efficiency, rapid excavation, robustness, mobility and flexible intelligent, unmanned boom-type roadheader robot.In this dissertation, boom-type roadheader robot control system architecture was proposed. Two key technical problems, including the cross-section forming and trajectory tracking, were analyzed. According to the robot tasks and operational process requirements, combined with the existing Higher Order Sliding Mode Control, some novel high-order sliding mode control methods were presented to achieve a cross-section forming and the robot trajectory tracking. The main study work can be generalized as follows:①A general structure for robot control system was presented. The mechanical structure and working principle of boom-type roadheader robot were analyzed. According to tasks and process requirements, functions and work processes of the robot's control system were analyzed and designed. The robot control system was decomposed into cutting arm control system and walking control system. The dynamics models of cutting arm and walking mechanism were presented, and some theoretical problems needed to be solved for control system were proposed.②Aim at the multiple variable, nonlinear problems and so on of the cutting arm control of boom-type roadheader robot system, higher-order sliding mode control and a class of second-order sliding mode control based on finite state machine strategy were analyzed. On the basic of an improved single-input single-output sub-optimal second-order sliding mode variable structure control based on finite state machine, several classes of second-order multi-variable sliding mode control for uncertain nonlinear systems were studied to extend it to several types of multi-input multi-output nonlinear control system effectively, and the sufficient condition for asymptotic stability of sliding mode variables were proved. Algorithms proposed were validated by simulation.③Aim at the high order nonlinear, uncertainty problems and so on of the walking control system of boom-type roadheader robot, Anosov Unstable (AU) and improved sub-optimal algorithm were combinated to present high-level sliding-mode control method based on finite state machine which solved the finite-time stabilization problem of a class of uncertain nonlinear systems with relative dregree three. The phase plane of sliding mode variable and its derivative and the phase plane of its derivative and its second-order derivative was analyzed to prove the stability of the algorithm and present the sufficient condition for sliding mode variable to converge in finite time. Proposed high-order sliding mode control method can force the sliding mode variable, its derivative and its second-order derivative to zero in finite time with the knowledge of the sliding mode variable and its derivative. Algorithms proposed were validated by simulation.④The cutting arm control system of boom-type roadheader robot was designed and implemented. According to tasks and process requirements, the cutting arm stroke was analyized during the cross-section forming process and the cutting header trajectory was designed. According to robot characteristics, geometric relationship of robot was established. The conversion between various coordinate systems was analyzed. According to robot's task requirements, the hardware system of cutting arm control system was built. Cutting arm controllers were designed and achieved by the proposed multiple-input multiple-output second-order sliding mode control method based on finite state machine. The simulation and experiments were carried out to validate the control system.⑤The track type walking control system of boom-type roadheader robot was designed and implemented. The steering and walking process of track type walking mechanism was analyzed. According to the actual robot operating environment constraints, the trajectory tracking control strategy was proposed. According to the characteristic of the track type walking mechanism, a layered control system architecture was proposed. The path planning strategy was designed. The hardware system of track type walking mechanism control system was built. The track postion controller was designed and achieved by the proposed high-level sliding-mode control method based on finite state machine for a class of uncertain nonlinear systems with relative dregree three.The simulation and experiments were carried out to validate the control system.Finally, the paper was summarized and the main research work and innovation point was presented. Boom-type roadheader robot and high-order sliding mode control were prospected.