IKPy问题: TypeError：__init__()缺少一个必需的位置参数：'origin_translation‘

Question

我试图在Python3.8中使用IKPy库(v3.3.3)在Mujoco平台上为我的机器人手臂编写一些演示。然而，当我尝试做的运动演示，有一些错误发生了如下所示。在这里输入图像描述下面是我的项目代码：

utils.py

from mujoco_py import MjViewer
import glfw

import numpy as np
import ikpy
from ikpy.chain import Chain
from ikpy.link import OriginLink, URDFLink

open_viewers = []  # a static list to keep track of all viewers


class MjViewerExtended(MjViewer):
    """ An extension of mujoco-py's MjViewer. MjViewerExtended does not
        terminate all other viewers and the python interpreter when closeing.
    """

    def __init__(self, sim):
        glfw.init()  # make sure glfw is initialized
        super().__init__(sim)
        open_viewers.append(self)

    def close(self):
        """ Closes the viewers glfw window. To open a new one, create a new
            instance of MjViewerExtended
        """
        # MjViewer only calls glfw.terminate() here killing glfw entierly.
        if glfw.window_should_close(self.window):
            return
        try:
            glfw.set_window_should_close(self.window, 1)
            glfw.destroy_window(self.window)
        except Exception:
            pass

        open_viewers.remove(self)
        if len(open_viewers) == 0:
            glfw.terminate()

    def key_callback(self, window, key, scancode, action, mods):
        if action == glfw.RELEASE and key == glfw.KEY_ESCAPE:
            self.close()
        else:
            super().key_callback(window, key, scancode, action, mods)


class Wam4IK(Chain):
    """ A basic kinamatic model of the MjWAM4 """

    def __init__(self, tool_orientation=None,
                 tool_translation=None,  # x, y, z
                 base_orientation=None,  # x, y, z
                 base_translation=None):

        if base_translation is None:
            base_translation = [0, 0, 0.84]
        if base_orientation is None:
            base_orientation = [0, 0, np.pi / 2]
        if tool_translation is None:
            tool_translation = [0, 0, 0]
        if tool_orientation is None:
            tool_orientation = [0, 0, 0]

        links = [OriginLink(),
                 URDFLink(name="wam/links/base",
                          translation=base_translation,  # translation of frame
                          origin_orientation=base_orientation,  # orientation of frame
                          rotation=[0, 0, 0]
                          ),  # joint axis [0, 0, 0] -> no joint
                 URDFLink(name="wam/links/shoulder_yaw",
                          translation=[0, 0, 0.16],
                          origin_orientation=[0, 0, 0],
                          rotation=[0, 0, 1]
                          ),
                 URDFLink(name="wam/links/shoulder_pitch",
                          translation=[0, 0, 0.186],
                          origin_orientation=[0, 0, 0],
                          rotation=[1, 0, 0]
                          ),
                 URDFLink(name="wam/links/shoulder_roll",
                          translation=[0, 0, 0],
                          origin_orientation=[0, 0, 0],
                          rotation=[0, 0, 1]
                          ),
                 URDFLink(name="wam/links/upper_arm",
                          translation=[0, -0.045, 0.550],
                          origin_orientation=[0, 0, 0],
                          rotation=[1, 0, 0]
                          ),
                 URDFLink(name="wam/links/tool_base_wo_plate",
                          translation=[0, 0.045, 0.350],
                          origin_orientation=[0, 0, 0],
                          rotation=[0, 0, 0]
                          ),
                 URDFLink(name="wam/links/tool_base_w_plate",
                          translation=[0, 0, 0.008],
                          origin_orientation=[0, 0, 0],
                          rotation=[0, 0, 0]
                          ),
                 URDFLink(name="wam/links/tool",
                          translation=tool_translation,
                          origin_orientation=tool_orientation,
                          rotation=[0, 0, 0]
                          )
                 ]

        self.all_joints = [False, False, True, True, True, True, False, False, False]
        self.active_joints = list(map(lambda x: x == 1, active_joints))
        self.active_links = [False, False, *self.active_joints, False, False, False]
        Chain.__init__(self, name='wam4',
                       active_links_mask=self.active_links,
                       links=links)

    def fk(self, joints, full_kinematics=False):
        joints = np.array([0, 0, *joints, 0, 0, 0])
        return Chain.forward_kinematics(self, joints, full_kinematics)

    def ik(self, target_position=None, target_orientation=None, orientation_mode=None, **kwargs):
        full = Chain.inverse_kinematics(self, target_position, target_orientation, orientation_mode, **kwargs)
        active = self.joints_from_links(full)
        return active

    def joints_from_links(self, joints):
        return np.compress(self.all_joints, joints, axis=0)

kinematics.py

import numpy as np
from mujoco_robots.utils import Wam4IK

import matplotlib.pyplot as plt
from mpl_toolkits import mplot3d

# from juggling_wams.envs import SingleArmOneBall
from mujoco_robots.robots import MjWam4


def plot_joints(chain, qs):
    fig = plt.figure()
    ax = fig.add_subplot(1, 1, 1, projection='3d', facecolor="1.0")
    for pos in qs:
        chain.plot([0, 0] + pos + [0, 0, 0], ax)
    plt.xlabel('x')
    plt.ylabel('y')
    plt.show()


def main():
    chain = Wam4IK(base_translation=[0, 0, 0.84],
                   base_orientation=[0, 0, np.pi / 2])

    links = ['wam/links/base',
             'wam/links/shoulder_yaw',
             'wam/links/shoulder_pitch',
             'wam/links/upper_arm',
             'wam/links/forearm',
             'wam/links/tool_base_wo_plate',
             'wam/links/tool_base_w_plate']

    x0 = np.array([0, 0, 0.84])
    q_test = [[0, 0, 0, 0], [1, 1, 1, 1]]

    robot = MjWam4(render=True, g_comp=True)
    for q in q_test:
        print(f'\n\ntesting for q={q}')
        robot.reset(pos=q)
        cart = chain.forward_kinematics([0, 0] + q + [0, 0, 0], full_kinematics=True)

        for i in range(7):
            print(f'\n{links[i][10:]}')
            mj_pos = robot.get_body_full_mat(links[i])[:3, 3] - x0
            ikpy_pos = cart[i + 1][:3, 3] - x0
            print(f'mj:   {mj_pos}')
            print(f'ikpy: {ikpy_pos}')
            print(f'diff: {mj_pos - ikpy_pos}')

    plot_joints(chain, q_test)

    # inverse kinematics
    x_des = [0.15, 0.86, 1.45]
    q = chain.active_from_full(chain.inverse_kinematics(x_des))
    robot.set_mocap_pos('endeff_des', x_des)
    robot.step(des_pos=q, n_steps=5000)


if __name__ == '__main__':
    main()

我认为我的环境设置和其他python文件没有问题。我认为问题应该发生在这两个文件中。如果你想看其他文件，我会很快上传它们。谢谢!

Answer 1

你打了几个这样的电话：

                 URDFLink(name="wam/links/shoulder_yaw",
                          translation=[0, 0, 0.16],
                          origin_orientation=[0, 0, 0],
                          rotation=[0, 0, 1]
                          ),

请务必指定强制的origin_translation参数。