仿人头颈部机器人跟踪运动控制

Tracking motion control method of humanoid head and neck robot

仿人头颈部机器人是仿人机器人的一部分,负责对视觉目标进行动态跟踪。为了能够精确跟踪目标,在系统运动学建模过程中,将机器人视场中心的视线作为一个具有伸缩自由度的连杆加入头颈部结构的运动学模型。通过双目视觉系统计算得到的目标点位置在数学模型上成为连杆机构运动的目标位置。为了使具有冗余自由度的头颈部机器人的运动更符合人类的动作行为,对用于消除运动学奇异点的阻尼最小二乘逆解算法进行了改进。改进后的修正算法不仅能够使机器人在运动过程中避开奇异点,而且能够实现算法上的关节限位,保证机器人运动的关节舒适度,使其更符合人类的行为习惯。仿真实验表明:这种算法在很大程度上提高了机器人运动的可靠性和稳定性。

Humanoid head and neck robot,which is part of humanoid robot,is responsible for dynamic visual target tracking.In order to be able to accurately track the target,the centre of the robot＇s sight field serves as stretch link in the kinematics model of the humanoid head and neck robot.The target position calculated by the binocular camera system is translated to the aim point,where the link mechanism moves to in the mathematic model.Damped least squares inverse kinematics method,which is used to eliminated the joint singularity,is modified to make the redundant humanoid head and neck robot moves like human being.The modified algorithm not only makes the robot to avoid the singularity in the movement,but also guarantees joint limit avoidance,comfortable joint movement and produces natural-looking postures.Simulation and experiment results show that the modified algorithm is more robust and stable.