七自由度番茄收获机械手的轨迹规划与仿真

为了探究番茄果实串收获机械手的轨迹规划方法，以七自由度番茄收获机械手为研究对象，运用D-H法建立运动学模型，得到位置和速度的正、反解.采用多项式插值法、抛物线过渡的线性插值法、摆线运动法和B样条插值法，对关节约束条件下的机械手，从复位点到采摘点的运动进行关节空间轨迹规划与仿真试验.分析关节运动的位移、速度和加速度，对不同规划方法的关节最大速度进行定量分析.利用五次多项式法和摆线运动法，研究末端执行器的位移和速度. 结果表明，利用五次多项式插值法能够满足关节路径点的位移、速度和加速度边界条件，规划的关节运动轨迹连续平滑，关节最大速度较摆线运动法平均降低了6.25%，提高了机械安全性能，对应的末端执行器运动轨迹平滑，无跳变点.

Trajectory planning and simulation for 7-DoF tomato harvesting manipulator

The seven degrees of freedom tomato harvesting manipulator was chosen as the research object in order to analyze the trajectory planning method of tomato cluster harvesting manipulator. The kinematics model was established by Denavit-Hartenberg (D-H) method, and the forward and inverse solutions of the position and velocity were calculated. Polynomial interpolation, linear interpolation with parabola transition, cycloid motion method and B-spline interpolation method were applied. Joint space trajectory planning and simulation experiments were conducted on the joint movement from the reset point to the picking point under the constraint condition of the joints. The displacement, velocity and acceleration of each joint were analyzed, and the maximum joint velocity of different planning methods was quantitatively analyzed. The displacement and velocity of the end effector were analyzed according to the quintic polynomial interpolation method and the cycloidal motion method. Results show that the quintic polynomial interpolation method meets the requirements of displacement, velocity and acceleration boundary conditions of path points. The planned joint trajectory is continuous and smooth, and the maximum joint velocity is reduced by 6.25% averagely compared with cycloidal motion method, which improves the mechanical safety performance. The corresponding end effector's movement trajectory is smooth and no jump point.