| import numpy as np |
| import scipy.interpolate as si |
| import scipy.spatial.transform as st |
|
|
|
|
| def get_interp1d(t, x): |
| gripper_interp = si.interp1d( |
| t, x, axis=0, bounds_error=False, fill_value=(x[0], x[-1]) |
| ) |
| return gripper_interp |
|
|
|
|
| class PoseInterpolator: |
| def __init__(self, t, x): |
| pos = x[:, :3] |
| rot = st.Rotation.from_rotvec(x[:, 3:]) |
| self.pos_interp = get_interp1d(t, pos) |
| self.rot_interp = st.Slerp(t, rot) |
|
|
| @property |
| def x(self): |
| return self.pos_interp.x |
|
|
| def __call__(self, t): |
| min_t = self.pos_interp.x[0] |
| max_t = self.pos_interp.x[-1] |
| t = np.clip(t, min_t, max_t) |
|
|
| pos = self.pos_interp(t) |
| rot = self.rot_interp(t) |
| rvec = rot.as_rotvec() |
| pose = np.concatenate([pos, rvec], axis=-1) |
| return pose |
|
|
|
|
| def get_gripper_calibration_interpolator(aruco_measured_width, aruco_actual_width): |
| """ |
| Assumes the minimum width in aruco_actual_width |
| is measured when the gripper is fully closed |
| and maximum width is when the gripper is fully opened |
| """ |
| aruco_measured_width = np.array(aruco_measured_width) |
| aruco_actual_width = np.array(aruco_actual_width) |
| assert len(aruco_measured_width) == len(aruco_actual_width) |
| assert len(aruco_actual_width) >= 2 |
| aruco_min_width = np.min(aruco_actual_width) |
| gripper_actual_width = aruco_actual_width - aruco_min_width |
| interp = get_interp1d(aruco_measured_width, gripper_actual_width) |
| return interp |
|
|
