To assemble a heavy payload to the spacecraft (free-floating base), the present study proposes a scheme of multiobjective trajectory planning for preimpact motion of redundant space manipulator (mounted on the base). Force impulse for self-assembly is derived as the function of joint angles/velocities, base pose, and impact direction. The trajectory planning problem is formulated as multiobjective optimization to minimize force impulse, base attitude disturbance, and energy consumption in the load-carrying process. A two-stage trajectory planning algorithm is proposed. To be specific, at the first stage, multiple desired configurations at the contact point are generated by position-level inverse kinematics with Newton–Raphson iterative method. At the second stage, joint trajectories satisfying joint angle limits and desired motion of the payload are parameterized by coefficients of sinusoidal polynomial functions. Multiobjective particle swarm optimization algorithm is adopted to solve the problem of multiobjective trajectory planning, and screening process is conducted to reserve nondominated solutions in limits of joint torques. The algorithm is implemented to a seven degrees of freedom space manipulator, and the effectiveness of the proposed method is verified by simulation results.

为了将沉重的载荷组装到航天器（自由浮动基座）上，本研究提出了一种用于冗余空间操纵器（安装在基座上）的预撞击运动的多目标轨迹规划方案。自组装的力脉冲是关节角度/速度，基础姿势和冲击方向的函数。轨迹规划问题被表述为多目标优化，以在承载过程中将力脉冲，基本姿态扰动和能耗降至最低。提出了一种两阶段轨迹规划算法。具体而言，在第一阶段，通过牛顿-拉夫森迭代法的位置级逆运动学在接触点处生成多个所需的构型。在第二阶段 满足关节角度限制和有效载荷的期望运动的关节轨迹通过正弦多项式函数的系数进行参数化。采用多目标粒子群优化算法解决了多目标轨迹规划问题，并进行了筛选过程以保留关节转矩极限内的非主导解。该算法在七自由度空间机械臂上实现，仿真结果验证了该方法的有效性。