水下焊接机器人弧线轨迹平顺运动控制策略

A smooth trajectory motion control strategy of underwater welding robot

在水下焊接机器人的弧线焊接过程中,为提高焊接质量、改善焊接效率,提出一种弧线轨迹平顺运动控制策略.首先建立焊接机器人的D-H数学模型,推导了机器人的正逆运动学公式,并简化了机器人正运动学公式;然后提出一种6维空间矢量法表示机器人末端的位姿;最后在笛卡尔空间下,采用带抛物线过渡的线性插值方法对机器人的空间位姿进行插补,合理规划了每个路径点对应焊接机器人各个关节的速度、加速度.采用以上控制策略进行水下焊接试验.结果表明,所得焊缝平整光滑,提高了焊接质量,缩短了焊接时间.

In the arc welding process of underwater welding robot,in order to improve the welding quality and the welding efficiency,a smooth trajectory control strategy was presented. Firstly,the mathematical model of the welding robot was established and the kinematics analysis was carried out by using the D-H parameter method. The forward kinematics and inverse kinematics formulas of the robot were deduced and the position formula of the robot was simplified. Then,the 6-dimensionalspace vector was proposed to represent the position and posture of the robot at each path point; Finally,a linear interpolation method with parabolic transition was used to interpolate the robot's space pose. At the same time,the speed and acceleration of each joint of the welding robot were calculated rationally,which can ensure a smooth welding process. The underwater welding experiment was carried out by using the above control strategy.The result showed that welding seam was smooth,and the welding quality was improved and the welding time was shortened.