Add IK types, validation, and tests for RM75 kinematics
This commit is contained in:
@ -1,809 +1,104 @@
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#!/usr/bin/env python3
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import sys
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import os
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"""Compatibility adapter for the original experimental import path.
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New code should import RM75Kinematics and RM75IkSolver from ``rm75_ik``.
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"""
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from math import pi
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from pathlib import Path
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import pinocchio as pin
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import numpy as np
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import osqp
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from scipy import sparse
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from math import radians, degrees, pi, cos, sin
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import time
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import threading
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import pinocchio as pin
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from rm75_ik import IkOptions, JointLimits, RM75IkSolver, RM75Kinematics
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class KinematicsSolver:
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def __init__(self, urdf_path="urdf_rm75/RM75-B.urdf", mesh_dir=None):
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del mesh_dir
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selected_path = Path(urdf_path)
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if not selected_path.is_file() and not selected_path.is_absolute():
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selected_path = Path(__file__).resolve().parent / selected_path
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self._urdf_path = selected_path
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self._limits = None
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self._tools = {}
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self._rebuild()
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class KinematicsSolver():
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def __init__(self,urdf_path="urdf_rm75/RM75-B.urdf", mesh_dir="urdf_rm75"):
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"""
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for realman 75b
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Initialize robotic arm kinematics using Pinocchio (ROS2 version).
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unit: m, rad
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"""
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print(f' ------------ the qp based kinematic initialising -----------')
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self.model, collision_model, visual_model = pin.buildModelsFromUrdf(urdf_path, mesh_dir)
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def _rebuild(self):
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self.kinematics = RM75Kinematics(self._urdf_path, self._limits)
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self.solver = RM75IkSolver(self.kinematics)
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self.model = self.kinematics.model
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self.data = self.kinematics.data
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def add_tool_frames(self, frames):
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for name, attributes in frames.items():
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pose = np.asarray(attributes[0], dtype=float)
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if pose.shape != (7,):
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raise ValueError(f"tool {name!r} pose must have seven values")
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quaternion = pin.Quaternion(pose[6], pose[3], pose[4], pose[5])
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quaternion.normalize()
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self._tools[name] = pin.SE3(quaternion.matrix(), pose[:3])
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self.cfg_j_limit()
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# ---------- for reused qp_solver ------------------
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self.nv = 7
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# Full dense symmetric matrix structure
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# P_template = np.triu(np.ones((7, 7)))
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self.P_pattern = sparse.triu(np.ones((7,7))).tocsc()
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P_sparse = sparse.csc_matrix(self.P_pattern)
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A_sparse = sparse.eye(7, format='csc')
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self.osqp_solver = osqp.OSQP()
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self.osqp_solver.setup(
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P=P_sparse,
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q=np.zeros(7),
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A=A_sparse,
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l=-np.ones(7),
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u=np.ones(7),
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verbose=False,
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warm_start=True,
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polish=False
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)
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self.W = np.diag([1, 1, 1, 0.4, 0.4, 0.4])
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def add_frame(self,frame_name, position, rotationXYZ):
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'''
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:param frame_name: str
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:param position: [x, y, z] target position (meters)
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:param rotationXYZ: [x, y, z] target rotation (rad)
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'''
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camera_rotation = pin.rpy.rpyToMatrix( rotationXYZ[0], rotationXYZ[1], rotationXYZ[2] )
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camera_offset = pin.SE3(
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camera_rotation,
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np.array(position)
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)
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self.model.addFrame( pin.Frame( frame_name, self.model.getJointId("joint_7"), self.model.getFrameId("link_7"), camera_offset, pin.FrameType.OP_FRAME ) )
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def add_tool_frames(self,dict_frames):
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self.tool_frames ={}
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for tool_name in dict_frames:
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tool_attr = dict_frames[tool_name]
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position = tool_attr[0][0:3]
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rotationXYZ = self.quaternion_to_euler(tool_attr[0][3:7])
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self.add_frame(tool_name, position, rotationXYZ)
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self.tool_frames.update({tool_name: self.model.getFrameId(tool_name)})
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self.data = self.model.createData()
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def cfg_j_limit(self, min_j=None, max_j=None, rad_flag = True):
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def cfg_j_limit(self, min_j=None, max_j=None, rad_flag=True):
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if min_j is None:
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min_j = [-3.14159, -2.2689, -3.14159, -2.3562, -3.14159, -2.234, -6.14159]
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min_j = [-pi, -2.2689, -pi, -2.3562, -pi, -2.234, -2 * pi]
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if max_j is None:
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max_j = [3.14159, 2.2689, 3.14159, 2.3562, 3.14159, 2.234, 6.14159]
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if rad_flag:
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for i in range(7):
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self.model.lowerPositionLimit[i] = min_j[i]
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self.model.upperPositionLimit[i] = max_j[i]
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else:
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for i in range(7):
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self.model.lowerPositionLimit[i] = min_j[i] / 180 * pi
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self.model.upperPositionLimit[i] = max_j[i] / 180 * pi
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max_j = [pi, 2.2689, pi, 2.3562, pi, 2.234, 2 * pi]
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lower = np.asarray(min_j, dtype=float)
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upper = np.asarray(max_j, dtype=float)
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if not rad_flag:
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lower = np.deg2rad(lower)
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upper = np.deg2rad(upper)
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self._limits = JointLimits("legacy", lower, upper)
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self._rebuild()
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def forward_kinematics(self, joint_angles, tool="omnipic"):
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"""
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Compute forward kinematics.
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def _tool(self, name):
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try:
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return self._tools[name]
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except KeyError as exc:
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raise ValueError(f"unknown tool frame: {name!r}") from exc
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Args:
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joint_angles: List or array of 7 joint angles (radians)
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tool: Name of frame to compute
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def forward_kinematics(self, joint_angles, tool="no_tool"):
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pose = self.kinematics.forward(np.asarray(joint_angles), self._tool(tool))
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return np.concatenate(
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[pose.translation.copy(), pin.rpy.matrixToRpy(pose.rotation)]
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)
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Returns:
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dict: Position, rotation, rpy, quaternion
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unit: position: m
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rpy: rad
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"""
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if len(joint_angles) != 7:
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raise ValueError(f"RM75 has 7 joints, got {len(joint_angles)}")
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# Create configuration vector
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q = pin.neutral(self.model)
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for i, angle in enumerate(joint_angles):
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q[i] = angle
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# Compute forward kinematics
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pin.forwardKinematics(self.model, self.data, q)
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pin.updateFramePlacements(self.model, self.data)
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# Get frame transform
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frame_id = self.tool_frames[tool]
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frame_transform = self.data.oMf[frame_id]
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# Extract results
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position = frame_transform.translation.copy()
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rotation = frame_transform.rotation.copy()
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# Compute RPY
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rpy = pin.rpy.matrixToRpy(rotation)
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# Compute quaternion
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# quat = pin.Quaternion(rotation)
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pose = np.concatenate([position, rpy], axis=0)
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return pose
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# return {
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# 'position': position,
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# # 'rotation': rotation,
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# 'rpy': rpy,
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# 'quaternion': [quat.x, quat.y, quat.z, quat.w],
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# # 'transform': frame_transform
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# }
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def inverse_kinematics(self, target_position, target_rpy=None,
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target_quat=None, initial_guess=None,
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max_iter=500, tolerance=5e-3, debug=False, tool="ee"):
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"""
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Compute inverse kinematics using differential IK with multiple strategies.
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Args:
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target_position: [x, y, z] target position (meters)
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target_rpy: [roll, pitch, yaw] target orientation (radians)
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target_quat: [x, y, z, w] target orientation as quaternion
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initial_guess: Initial joint angles (radians)
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max_iter: Maximum iterations
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tolerance: Error tolerance
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debug: Print debug information
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tool: the frame name ('scissor', 'camera', 'ee')
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Returns:
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tuple: (joint_angles, success, error)
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"""
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# Build target SE3 placement
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def inverse_kinematics(
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self,
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target_position,
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target_rpy=None,
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target_quat=None,
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initial_guess=None,
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max_iter=500,
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tolerance=1e-3,
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debug=False,
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tool="no_tool",
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):
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del debug
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if target_quat is not None:
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quat = pin.Quaternion(target_quat[3], target_quat[0], target_quat[1], target_quat[2])
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target_rotation = quat.matrix()
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values = np.asarray(target_quat, dtype=float)
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quaternion = pin.Quaternion(values[3], values[0], values[1], values[2])
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rotation = quaternion.matrix()
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elif target_rpy is not None:
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target_rotation = pin.rpy.rpyToMatrix(target_rpy[0],
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target_rpy[1],
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target_rpy[2])
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rotation = pin.rpy.rpyToMatrix(*target_rpy)
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else:
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target_rotation = np.eye(3)
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target_placement = pin.SE3(target_rotation, np.array(target_position))
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# Try multiple initial guesses
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initial_guesses = []
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if initial_guess is not None:
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initial_guesses.append(initial_guess)
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else:
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# Try different initial configurations
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initial_guesses.append([0.1] * 7) # Zero config
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best_solution = None
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best_error = float('inf')
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for guess_idx, guess in enumerate(initial_guesses):
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q = pin.neutral(self.model)
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for i, angle in enumerate(guess):
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if i < len(q):
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q[i] = np.clip(angle, self.model.lowerPositionLimit[i],
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self.model.upperPositionLimit[i])
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q_ref = q.copy()
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# Differential IK with adaptive damping
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damping = 0.1
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damping_reduction = 0.95
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iter_count = 0
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prev_error = float('inf')
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ee_frame_id = self.tool_frames[tool]
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J = pin.computeFrameJacobian(
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self.model,
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self.data,
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q,
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ee_frame_id,
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pin.ReferenceFrame.LOCAL
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)
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pin.forwardKinematics(self.model, self.data, q)
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pin.updateFramePlacements(self.model, self.data)
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current_placement = self.data.oMf[ee_frame_id]
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error_SE3 = current_placement.actInv(target_placement)
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error_vec = pin.log(error_SE3).vector
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# print("\n initial error =", np.linalg.norm(error_vec))
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# print(error_vec)
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while iter_count < max_iter:
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# Compute forward kinematics
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pin.computeJointJacobians(self.model, self.data, q)
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pin.framesForwardKinematics(self.model, self.data, q)
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# Get current end-effector placement
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current_placement = self.data.oMf[ee_frame_id]
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# Compute error
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error_SE3 = current_placement.actInv(target_placement)
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error_vec = pin.log(error_SE3).vector
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error_norm = np.linalg.norm(error_vec)
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if error_norm < tolerance:
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if error_norm < best_error:
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best_error = error_norm
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best_solution = q[:7].copy()
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break
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# Check if error is increasing (diverging)
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if error_norm > prev_error * 1.1 and iter_count > 10:
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damping = min(1.0, damping * 1.5)
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else:
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damping = max(0.01, damping * damping_reduction)
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J = pin.getFrameJacobian(
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self.model,
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self.data,
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ee_frame_id,
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pin.ReferenceFrame.LOCAL
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)
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# =========================
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# QP-based IK
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# =========================
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w_posture = 0.0001
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J_eff = pin.Jlog6(error_SE3) @ J #J #
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H = J_eff.T @ self.W @ J_eff
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# H = J.T @ self.W @ J
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H += damping * damping * np.eye(7)
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H += w_posture * np.eye(7)
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H_triu = sparse.triu(H).tocsc()
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g = -J_eff.T @ self.W @ error_vec
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g += w_posture * (q[:7] - q_ref[:7])
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# g = - J.T @ self.W @ error_vec
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# -------------------------
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# Joint velocity constraints
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# -------------------------
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dq_limit = 0.05 # rad per iteration
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lb = -dq_limit * np.ones(7)
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ub = dq_limit * np.ones(7)
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# -------------------------
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# Joint position constraints
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# -------------------------
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q_min_step = self.model.lowerPositionLimit[:7] - q[:7]
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q_max_step = self.model.upperPositionLimit[:7] - q[:7]
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lb = np.maximum(lb, q_min_step)
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ub = np.minimum(ub, q_max_step)
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# -------------------------
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# Solve QP
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# ------------------------
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# Update solver
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self.osqp_solver.update(
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Px= H_triu.data, #H[np.triu_indices(7)], #
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q=g,
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l=lb,
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u=ub
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)
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# Solve
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result = self.osqp_solver.solve()
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if result.info.status != 'solved':
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break
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dq = result.x
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if dq is None:
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break
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# Apply joint limits with scaling
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alpha = 1.0
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q = pin.integrate(self.model, q, alpha * dq)
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prev_error = error_norm
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iter_count += 1
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if best_solution is not None:
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# return best_solution, True, best_error, iter_count
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return 0, best_solution.tolist()
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else:
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# return q[:7].copy(), False, error_norm, iter_count
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return -1, q[:7].copy().tolist()
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def quaternion_to_euler(self, q):
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"""
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Convert quaternion to Euler angles (roll, pitch, yaw)
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Args:
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qx, qy, qz, qw: quaternion components
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Returns:
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tuple: (roll, pitch, yaw) in radians
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"""
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# Roll (x-axis rotation)
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sinr_cosp = 2.0 * (q[3] * q[0] + q[1] * q[2])
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cosr_cosp = 1.0 - 2.0 * (q[0] * q[0] + q[1] * q[1])
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roll = np.arctan2(sinr_cosp, cosr_cosp)
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# Pitch (y-axis rotation)
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sinp = 2.0 * (q[3] * q[1] - q[2] * q[0])
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if abs(sinp) >= 1:
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pitch = np.copysign(np.pi / 2, sinp) # Use 90 degrees if out of range
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else:
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pitch = np.arcsin(sinp)
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# Yaw (z-axis rotation)
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siny_cosp = 2.0 * (q[3] * q[2] + q[0] * q[1])
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cosy_cosp = 1.0 - 2.0 * (q[1] * q[1] + q[2] * q[2])
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yaw = np.arctan2(siny_cosp, cosy_cosp)
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return [roll, pitch, yaw]
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# def invese_kinematics_velocity(self, target_position, target_rpy=None,
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# target_quat=None, initial_guess=None, tool="ee"):
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# """
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# Compute the converging velocity (motion direction) of joints based on qp inverse kinematics.
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#
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# Args:
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# target_position: [x, y, z] target position (meters)
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# target_rpy: [roll, pitch, yaw] target orientation (radians)
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# target_quat: [x, y, z, w] target orientation as quaternion
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# initial_guess: Initial joint angles (radians)
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# tool: the frame name ('scissor', 'camera', 'ee')
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#
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# Returns:
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# joint_velocity: np.array()
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# """
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# # Build target SE3 placement
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# if target_quat is not None:
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# quat = pin.Quaternion(target_quat[3], target_quat[0],
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# target_quat[1], target_quat[2])
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# target_rotation = quat.matrix()
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# elif target_rpy is not None:
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# target_rotation = pin.rpy.rpyToMatrix(target_rpy[0],
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# target_rpy[1],
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# target_rpy[2])
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# else:
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# target_rotation = np.eye(3)
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#
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# target_placement = pin.SE3(target_rotation, np.array(target_position))
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#
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# # Try multiple initial guesses
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# initial_guesses = []
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#
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# if initial_guess is not None:
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# initial_guesses.append(initial_guess)
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# else:
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# # Try different initial configurations
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# initial_guesses.append([0.1] * 7) # Zero config
|
||||
# initial_guesses.append([radians(30), radians(45), radians(30),
|
||||
# radians(-45), radians(30), radians(-30), 0])
|
||||
# initial_guesses.append([radians(-30), radians(45), radians(-30),
|
||||
# radians(45), radians(30), radians(30), 0])
|
||||
#
|
||||
# best_solution = None
|
||||
# best_error = float('inf')
|
||||
#
|
||||
# for guess_idx, guess in enumerate(initial_guesses):
|
||||
# q = pin.neutral(self.model)
|
||||
# for i, angle in enumerate(guess):
|
||||
# if i < len(q):
|
||||
# q[i] = np.clip(angle, self.model.lowerPositionLimit[i],
|
||||
# self.model.upperPositionLimit[i])
|
||||
#
|
||||
# # Differential IK with adaptive damping
|
||||
# damping = 0.01
|
||||
# damping_reduction = 0.95
|
||||
# iter_count = 0
|
||||
# prev_error = float('inf')
|
||||
#
|
||||
# ee_frame_id = self.tool_frames[tool]
|
||||
#
|
||||
# J = pin.computeFrameJacobian(
|
||||
# self.model,
|
||||
# self.data,
|
||||
# q,
|
||||
# ee_frame_id,
|
||||
# pin.ReferenceFrame.LOCAL_WORLD_ALIGNED
|
||||
# )
|
||||
#
|
||||
# while iter_count < max_iter:
|
||||
# # Compute forward kinematics
|
||||
#
|
||||
# pin.computeJointJacobians(self.model, self.data, q)
|
||||
# pin.framesForwardKinematics(self.model, self.data, q)
|
||||
#
|
||||
# # Get current end-effector placement
|
||||
#
|
||||
# current_placement = self.data.oMf[ee_frame_id]
|
||||
#
|
||||
# # Compute error
|
||||
# error_SE3 = current_placement.actInv(target_placement)
|
||||
# error_vec = pin.log(error_SE3).vector
|
||||
# error_norm = np.linalg.norm(error_vec)
|
||||
#
|
||||
# if error_norm < tolerance:
|
||||
# joint_angles = q[:7].copy()
|
||||
# fk_result = self.forward_kinematics(joint_angles, tool=tool)
|
||||
# position_error = np.linalg.norm(fk_result['position'] - np.array(target_position))
|
||||
#
|
||||
# if position_error < best_error:
|
||||
# best_error = position_error
|
||||
# best_solution = joint_angles
|
||||
# break
|
||||
#
|
||||
# # Check if error is increasing (diverging)
|
||||
# if error_norm > prev_error * 1.1 and iter_count > 10:
|
||||
# damping = min(1.0, damping * 1.5)
|
||||
# else:
|
||||
# damping = max(0.01, damping * damping_reduction)
|
||||
#
|
||||
# J = pin.getFrameJacobian(
|
||||
# self.model,
|
||||
# self.data,
|
||||
# ee_frame_id,
|
||||
# pin.ReferenceFrame.LOCAL_WORLD_ALIGNED
|
||||
# )
|
||||
#
|
||||
# # =========================
|
||||
# # QP-based IK
|
||||
# # =========================
|
||||
#
|
||||
# H = J.T @ self.W @ J
|
||||
# H += damping * damping * np.eye(7)
|
||||
#
|
||||
# H_triu = sparse.triu(H).tocsc()
|
||||
#
|
||||
# g = -J.T @ self.W @ error_vec
|
||||
#
|
||||
# # -------------------------
|
||||
# # Joint velocity constraints
|
||||
# # -------------------------
|
||||
#
|
||||
# dq_limit = 0.05 # rad per iteration
|
||||
#
|
||||
# lb = -dq_limit * np.ones(7)
|
||||
# ub = dq_limit * np.ones(7)
|
||||
#
|
||||
# # -------------------------
|
||||
# # Joint position constraints
|
||||
# # -------------------------
|
||||
#
|
||||
# q_min_step = self.model.lowerPositionLimit[:7] - q[:7]
|
||||
# q_max_step = self.model.upperPositionLimit[:7] - q[:7]
|
||||
#
|
||||
# lb = np.maximum(lb, q_min_step)
|
||||
# ub = np.minimum(ub, q_max_step)
|
||||
#
|
||||
# # -------------------------
|
||||
# # Solve QP
|
||||
# # ------------------------
|
||||
# # Update solver
|
||||
# self.osqp_solver.update(
|
||||
# Px=H_triu.data,
|
||||
# q=g,
|
||||
# l=lb,
|
||||
# u=ub
|
||||
# )
|
||||
#
|
||||
# # Solve
|
||||
# result = self.osqp_solver.solve()
|
||||
#
|
||||
# if result.info.status != 'solved':
|
||||
# break
|
||||
#
|
||||
# dq = result.x
|
||||
#
|
||||
# if dq is None:
|
||||
# break
|
||||
#
|
||||
# # Apply joint limits with scaling
|
||||
# alpha = 0.5
|
||||
# q = pin.integrate(self.model, q, alpha * dq)
|
||||
#
|
||||
# prev_error = error_norm
|
||||
# iter_count += 1
|
||||
#
|
||||
# if best_solution is not None:
|
||||
# return best_solution, True, best_error
|
||||
# else:
|
||||
# return None, False, None
|
||||
|
||||
def compute_jacobian(self, joint_angles, tool="ee"):
|
||||
"""Compute geometric Jacobian (6x7)"""
|
||||
q = pin.neutral(self.model)
|
||||
for i, angle in enumerate(joint_angles):
|
||||
q[i] = angle
|
||||
|
||||
pin.forwardKinematics(self.model, self.data, q)
|
||||
pin.updateFramePlacements(self.model, self.data)
|
||||
ee_frame_id = self.tool_frames[tool]
|
||||
J = pin.computeFrameJacobian(self.model, self.data, q, ee_frame_id)
|
||||
|
||||
return J
|
||||
|
||||
def get_subchain_jacobian(self,
|
||||
joint_angles,
|
||||
frame_names
|
||||
):
|
||||
|
||||
q = pin.neutral(self.model)
|
||||
|
||||
all_active_joints = self.get_active_joints_from_frame(frame_names)
|
||||
|
||||
for i in range(7):
|
||||
q[i] = joint_angles[i]
|
||||
|
||||
pin.forwardKinematics(self.model, self.data, q)
|
||||
pin.updateFramePlacements(self.model, self.data)
|
||||
pin.computeJointJacobians(self.model, self.data, q)
|
||||
|
||||
Js = []
|
||||
|
||||
for frame_name, active_joints in zip(frame_names, all_active_joints):
|
||||
frame_id = self.model.getFrameId(frame_name)
|
||||
|
||||
J = pin.getFrameJacobian(
|
||||
self.model,
|
||||
self.data,
|
||||
frame_id,
|
||||
pin.ReferenceFrame.LOCAL
|
||||
)
|
||||
Js.append(J[:, active_joints])
|
||||
|
||||
return Js
|
||||
|
||||
def get_active_joints_from_frame(self, frame_names):
|
||||
"""
|
||||
Return active joint indices affecting a frame.
|
||||
|
||||
Example:
|
||||
frame_name='link_4'
|
||||
-> [0,1,2,3]
|
||||
"""
|
||||
all_active_joint_ids = []
|
||||
for frame_name in frame_names:
|
||||
frame_id = self.model.getFrameId(frame_name)
|
||||
|
||||
# Parent joint of this frame
|
||||
joint_id = self.model.frames[frame_id].parentJoint
|
||||
|
||||
print(f'frame_id = {frame_id}, and joint_id = {joint_id}')
|
||||
|
||||
active_joint_ids = []
|
||||
|
||||
|
||||
# Traverse upward to root
|
||||
while joint_id > 0:
|
||||
# Pinocchio joint indexing:
|
||||
# universe joint = 0
|
||||
# robot joints start from 1
|
||||
|
||||
active_joint_ids.append(joint_id - 1)
|
||||
|
||||
# Move to parent joint
|
||||
joint_id = self.model.parents[joint_id]
|
||||
|
||||
# Reverse so order becomes base -> tip
|
||||
active_joint_ids.reverse()
|
||||
all_active_joint_ids.append(active_joint_ids)
|
||||
|
||||
return all_active_joint_ids
|
||||
|
||||
def plan_cartesian_trajectory(self, start_pos, end_pos,
|
||||
start_rpy=None, end_rpy=None,
|
||||
num_steps=20, tool='ee'):
|
||||
"""
|
||||
Plan a Cartesian trajectory with IK for each waypoint.
|
||||
"""
|
||||
# Get current end-effector pose if start_rpy not provided
|
||||
if start_rpy is None:
|
||||
# Try to find a valid starting configuration
|
||||
test_angles = [0.1] * 7
|
||||
fk_test = self.forward_kinematics(test_angles,tool=tool)
|
||||
start_rpy = fk_test['rpy']
|
||||
|
||||
if end_rpy is None:
|
||||
end_rpy = start_rpy
|
||||
|
||||
# First, check if target is reachable
|
||||
print(f"\nChecking if target is reachable...")
|
||||
target_pos = end_pos
|
||||
target_rpy = end_rpy
|
||||
|
||||
test_solution, success, error = self.inverse_kinematics(
|
||||
target_pos, target_rpy=target_rpy, initial_guess=[0.1] * 7, max_iter=500, tool=tool
|
||||
rotation = np.eye(3)
|
||||
tool_pose = self._tool(tool)
|
||||
target_tool = pin.SE3(rotation, np.asarray(target_position, dtype=float))
|
||||
target_flange = target_tool * tool_pose.inverse()
|
||||
seed = np.zeros(7) if initial_guess is None else np.asarray(initial_guess, dtype=float)
|
||||
result = self.solver.solve(
|
||||
target_flange,
|
||||
seed,
|
||||
IkOptions(
|
||||
position_tolerance_m=tolerance,
|
||||
orientation_tolerance_rad=tolerance,
|
||||
max_iterations=max_iter,
|
||||
),
|
||||
)
|
||||
return (0, result.q.tolist()) if result.success else (-1, [])
|
||||
|
||||
if not success:
|
||||
print(f"Warning: Target may be unreachable or difficult to reach")
|
||||
print(f"Trying with relaxed tolerance...")
|
||||
|
||||
# Initial guess for IK (start with zero configuration)
|
||||
current_angles = [0.1] * 7
|
||||
trajectory = []
|
||||
|
||||
print(f"\nPlanning trajectory from ({start_pos[0]:.2f}, {start_pos[1]:.2f}, {start_pos[2]:.2f})")
|
||||
print(f"To ({end_pos[0]:.2f}, {end_pos[1]:.2f}, {end_pos[2]:.2f})")
|
||||
print("-" * 60)
|
||||
|
||||
for i in range(num_steps + 1):
|
||||
t = i / num_steps
|
||||
|
||||
# Interpolate position
|
||||
pos = [
|
||||
start_pos[0] + t * (end_pos[0] - start_pos[0]),
|
||||
start_pos[1] + t * (end_pos[1] - start_pos[1]),
|
||||
start_pos[2] + t * (end_pos[2] - start_pos[2])
|
||||
]
|
||||
|
||||
# Interpolate orientation
|
||||
rpy = [
|
||||
start_rpy[0] + t * (end_rpy[0] - start_rpy[0]),
|
||||
start_rpy[1] + t * (end_rpy[1] - start_rpy[1]),
|
||||
start_rpy[2] + t * (end_rpy[2] - start_rpy[2])
|
||||
]
|
||||
|
||||
# Compute IK
|
||||
joint_angles, success, error = self.inverse_kinematics(
|
||||
pos, target_rpy=rpy, initial_guess=current_angles, max_iter=300, tool=tool
|
||||
)
|
||||
|
||||
if not success:
|
||||
print(f" Waypoint {i}: IK failed!")
|
||||
break
|
||||
|
||||
# Verify
|
||||
fk_verify = self.forward_kinematics(joint_angles, tool=tool)
|
||||
|
||||
trajectory.append({
|
||||
'step': i,
|
||||
't': t,
|
||||
'position': pos,
|
||||
'rpy': rpy,
|
||||
'joint_angles': joint_angles,
|
||||
'actual_position': fk_verify['position'],
|
||||
'error': error
|
||||
})
|
||||
|
||||
# Update current angles for next iteration
|
||||
current_angles = joint_angles
|
||||
|
||||
if i % 5 == 0 or i == num_steps:
|
||||
print(f" Waypoint {i:3d}: pos=({pos[0]:.3f}, {pos[1]:.3f}, {pos[2]:.3f}), "
|
||||
f"error={error:.6f}m")
|
||||
|
||||
return trajectory
|
||||
|
||||
|
||||
|
||||
def main():
|
||||
"""Main test function"""
|
||||
|
||||
|
||||
rm75 = KinematicsSolver()
|
||||
|
||||
# Test 1: Forward Kinematics
|
||||
print("\n1. Forward Kinematics Test")
|
||||
print("-" * 40)
|
||||
|
||||
tool_name = "scissor"
|
||||
joint_angles_zero = [0.1] * 7
|
||||
fk_result = rm75.forward_kinematics(joint_angles_zero, tool=tool_name)
|
||||
|
||||
print(f"Init configuration:")
|
||||
print(f" Position: ({fk_result['position'][0]:.3f}, "
|
||||
f"{fk_result['position'][1]:.3f}, {fk_result['position'][2]:.3f}) m")
|
||||
|
||||
# Test 2: Inverse Kinematics with more reachable target
|
||||
print("\n2. Inverse Kinematics Test")
|
||||
print("-" * 40)
|
||||
|
||||
# Try a simpler target first
|
||||
target_pos = [0.3, 0.2, 0.4] # More reachable position
|
||||
target_rpy = [0.0, 0.0, radians(45)] # Simpler orientation
|
||||
|
||||
print(f"Target: ({target_pos[0]:.3f}, {target_pos[1]:.3f}, {target_pos[2]:.3f}) m")
|
||||
|
||||
import time
|
||||
init_joints = [0.2] * 7
|
||||
time0 = time.time()
|
||||
for ii in range(100):
|
||||
joint_solution, success, error = rm75.inverse_kinematics(
|
||||
target_pos, target_rpy=target_rpy, initial_guess=init_joints,
|
||||
max_iter=500, debug=False, tool=tool_name
|
||||
)
|
||||
time1 = time.time()
|
||||
print(f"Time: {time1 - time0}")
|
||||
|
||||
if success:
|
||||
print(f"✓ Solution found! Error: {error:.6f} m")
|
||||
for i, angle in enumerate(joint_solution):
|
||||
print(f" Joint {i + 1}: {degrees(angle):7.2f}°")
|
||||
|
||||
# Verify
|
||||
fk_verify = rm75.forward_kinematics(joint_solution,tool=tool_name)
|
||||
print(
|
||||
f" Position: ({fk_verify['position'][0]:.3f}, {fk_verify['position'][1]:.3f}, {fk_verify['position'][2]:.3f}) m")
|
||||
else:
|
||||
print("✗ IK failed to find a solution!")
|
||||
|
||||
# Test 3: Jacobian
|
||||
print("\n3. Jacobian Matrix")
|
||||
print("-" * 40)
|
||||
|
||||
J = rm75.compute_jacobian(joint_angles_zero, tool=tool_name)
|
||||
print(f"Jacobian shape: {J.shape}")
|
||||
for i in range(min(3, J.shape[0])):
|
||||
row_str = " ".join([f"{J[i, j]:7.3f}" for j in range(7)])
|
||||
print(f" Row {i + 1}: {row_str}")
|
||||
|
||||
# Test 4: Trajectory Planning with reachable positions
|
||||
print("\n4. Cartesian Trajectory Planning")
|
||||
print("-" * 40)
|
||||
|
||||
start_pos = [0.3, 0.0, 0.4] # Start position
|
||||
end_pos = [0.3, 0.0, 0.55] # End position (smaller movement)
|
||||
|
||||
fk0 = rm75.forward_kinematics([0.1] * 7, tool=tool_name)
|
||||
|
||||
trajectory = rm75.plan_cartesian_trajectory(
|
||||
start_pos,
|
||||
end_pos,
|
||||
start_rpy=fk0['rpy'],
|
||||
end_rpy=[
|
||||
fk0['rpy'][0] + radians(10),
|
||||
fk0['rpy'][1],
|
||||
fk0['rpy'][2]
|
||||
],
|
||||
num_steps=10,
|
||||
tool=tool_name
|
||||
)
|
||||
|
||||
if trajectory:
|
||||
print(f"\n✓ Generated {len(trajectory)} waypoints")
|
||||
|
||||
if success:
|
||||
print("✓ Inverse kinematics working (with simplified target)")
|
||||
else:
|
||||
print("⚠ Inverse kinematics may need tuning - try different targets")
|
||||
|
||||
|
||||
print("\n" + "=" * 60)
|
||||
print(f'test subchain Jacobian, for future obstacle avoidance')
|
||||
frame_names = [
|
||||
"link_2",
|
||||
"link_4",
|
||||
"link_7"
|
||||
]
|
||||
Js_sub = rm75.get_subchain_jacobian(
|
||||
joint_angles=joint_angles_zero,
|
||||
frame_names=frame_names
|
||||
)
|
||||
print(f'Js_sub: {Js_sub}')
|
||||
|
||||
return rm75, trajectory
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
rm75, trajectory = main()
|
||||
|
||||
print("\n" + "=" * 60)
|
||||
print("All tests completed!")
|
||||
print("=" * 60)
|
||||
def compute_jacobian(self, joint_angles, tool="no_tool"):
|
||||
del tool
|
||||
return self.kinematics.jacobian(np.asarray(joint_angles, dtype=float))
|
||||
|
||||
Reference in New Issue
Block a user