【作者】 淮小利；

【导师】 王培光；

【作者基本信息】 河北大学 ， 检测技术与自动化装置， 2008， 硕士

【摘要】 本文主要针对机器人视觉伺服控制进行了研究,基于当前视觉伺服控制领域的不同问题提出了相关的控制算法,主要包括基于图像雅可比矩阵的视觉控制器、基于单应性矩阵的视觉控制器、基于仿射近似的视觉控制器和基于切换方法的视觉控制器。(1)应用图像雅可比矩阵理论,以PUMA560机器人为试验研究对象,在matlab/simulink环境下搭建了视觉伺服系统仿真平台,完成了伺服系统仿真及控制器的验证工作。(2)设计了基于单应性矩阵的视觉控制器,该方法克服了图像雅可比矩阵方法的局部线性化缺陷,扩大了机器人的应用范围,而且避开了图像深度信息的求取,当环境噪声影响较小时可获得较高的控制精度；针对机械臂作纯仿射运动的情况,即不包含绕X轴或Y轴的旋转,设计了基于仿射近似的视觉控制器,该控制器当环境中存在较大噪声时仍能获得较好的控制性能,因此该方法对噪声具有较强的鲁棒性。(3)为了克服以上控制器对应用环境的局限性,本文结合了以上控制器的优点,将切换方法引入到机器人视觉伺服系统中。切换控制器由两个或两个以上的子控制器和一个上层的决策控制器组成,决策控制器通过一组切换规则来选择视觉控制器,使系统得到更好的伺服效果。本文将基于单应性矩阵的控制器和基于仿射近似的控制器作为子控制器,选择一组切换规则,在两个子控制器之间切换,充分利用两个子控制器的优点,优势互补。并以六自由度的PUMA560机器人为例,通过控制机械臂抓取空间物体这一任务进行了验证,仿真结果表明所设计的控制器能够快速高效的完成伺服任务。更多还原

【Abstract】 In this article, our research mainly aims at the control problems existing in robot visual system. According to the problems existed, we put forward relevant control algorithms, including, image jacobian based visual servo controller, homography based controller, affine approximation controller and switched controller.(1) By applying the theory of image jacobian matrix to PUMA560 robot, we build the simulation platform of visual servo system, and realize system simulation and validation of the controller designed.(2) A homography based controller is designed in this article. This method enlarges robot’s application area, avoids the depth information and with high precision when noise in circumstance is weak. Furthermore, when robot does pure affine motion, which do not include the rotation around X or Y axis, we design the affine approximation controller. This can also works well when strong noise exists, so this controller has strong robustness to noise.(3) In order to conquer the limit of above controllers to circumstance, we combine the advantages of above controllers and apply switching approach to robot visual servo system. Switched controller is comprised of several sub-controllers and a group of switching rules which switches between them.In this article, we use homography based controller and affine approximation controller as sub-controllers. Then we choose a group of switching rules which are responsible of switching between them, so we can take full advantages of two controllers. At last, we do an experiment on PUMA560 robot which has six degrees, and the simulation results show that the controllers we designed can complete servo task quickly and efficiently.更多还原