在使用roboticstoolbox-python计算关节扭矩时

import roboticstoolbox as rtb
import numpy as np
robot = rtb.models.UR10()
q = np.array([0, -np.pi/4, np.pi/4, 0, np.pi/4, 0])
qd = np.array([0, 0, 0, 0, 0, 0])
qdd = np.array([0, 0, 0, 0, 0, 0])
robot.gravity = [0, 0, -9.81]
try:
    torques = robot.rne(q, qd, qdd)
    print("Calculated joint torques:", torques)
except Exception as e:
    print("Error while calculating torques:", e)

对于URDF定义的机械臂可能会遇到下面报错：

list indices must be integers or slices, not NoneType

这是因为当前官方版本的rne函数存在bug，固定关节的机器人会遇到次bug。

但是此bug已经有人修复，官方尚未合并，请移步官方仓库Pull requests查看：Fixing RNE for URDFs robots with fixed joints #408