基于线特征与内区域特征的视觉伺服解耦控制

针对多自由度机械臂快速趋近任意四边形态目标的视觉伺服控制难题,提出了结合线特征与内区域特征的机器人视觉伺服解耦控制方法.构建了目标内区域特征以指导相机的平移运动速率,利用目标的线特征给出相机的旋转角速率,并通过引入内区域特征的矢量补偿和质心坐标的位置补偿,实现了平移和旋转控制的部分解耦.最后,对机器人视觉伺服控制系统进行了稳定性分析.仿真验证结果表明所提方法能控制相机以较快而平滑的动作收敛到期望位姿,且在相机光轴与目标平面近似垂直的条件下能较好地克服深度估计造成的不确定性问题.

Visual Servoing Decoupling Control Based on Line Features and Inner-region Based Features

To solve the problem for a multi-degree-of-freedom manipulator approaching an arbitrary quadrilateral target, we propose a method of combining line features and inner-region based features to achieve a robotic decoupled visual servoing (VS)process. We build the inner-region based features to guide the camera's translational velocities, while using the target's line features to generate the camera's rotational angular velocities, and then introduce a vector compensation for the inner-region based features and a position compensation for the centroid coordinates, resulting in a partially decoupling of the camera translational and rotational control. Finally, we carry out the stability analysis of the robotic VS control system. Simulation results show that the propose method can control the camera to converge to the desired pose with faster and smoother motion, and can better overcome the uncertainty caused by depth estimation under the condition that the camera optical axis is approximately perpendicular to the target plane.