roll, pitch, yaw = np.rad2deg(np.squeeze(np.array( np.quaternion(qw, qx, qy, qz).normalized().to_euler_angles('xyz') )))

这行代码的作用是将四元数转换为欧拉角，其中：

- `np.quaternion(qw, qx, qy, qz)` 创建了一个四元数对象，其四个分量为 qw、qx、qy、qz。
- `.normalized()` 将四元数归一化，确保其长度为1。
- `.to_euler_angles('xyz')` 将四元数转换为欧拉角，其中 'xyz' 表示欧拉角的顺序。
- `np.squeeze(np.array(...))` 将欧拉角转换为numpy数组，并通过 `squeeze` 函数去掉其中的单维度。
- `np.rad2deg(...)` 将弧度制的欧拉角转换为角度制。

最终，这行代码返回了三个变量，分别为 roll、pitch 和 yaw，表示物体绕 X、Y、Z 轴的旋转角度，单位为角度。需要注意的是，在使用四元数计算欧拉角时，需要将四元数进行归一化，以确保其长度为1，否则计算出来的欧拉角可能不正确。

相关问题

#!/usr/bin/env python3 # -*- coding: utf-8 -*- import rospy import math import numpy as np from grasp_demo.srv import * def tf_transform(req): tool_h_cam = np.array([[1.0, 0.0, 0, -0.010], [0.0, -1.0, 0.0, -0.018], [0.0, 0.0, -1.0, 0.1], [0.0, 0.0, 0.0, 1.0] ]) cam_h_obj = np.array([[req.marker_x], [req.marker_y], [req.marker_z], [1]]) r_x = np.array([[1, 0, 0], [0, math.cos(req.robot_roll), -math.sin(req.robot_roll)], [0, math.sin(req.robot_roll), math.cos(req.robot_roll)] ]) r_y = np.array([[math.cos(req.robot_pitch), 0, math.sin(req.robot_pitch)], [0, 1, 0], [-math.sin(req.robot_pitch), 0, math.cos(req.robot_pitch)] ]) r_z = np.array([[math.cos(req.robot_yaw), -math.sin(req.robot_yaw), 0], [math.sin(req.robot_yaw), math.cos(req.robot_yaw), 0], [0, 0, 1] ]) r = np.dot(r_z, np.dot(r_y, r_x)) base_h_tool = np.array([[r[0, 0], r[0, 1], r[0, 2], req.robot_x], [r[1, 0], r[1, 1], r[1, 2], req.robot_y], [r[2, 0], r[2, 1], r[2, 2], req.robot_z], [0, 0, 0, 1] ]) print(base_h_tool) kk = np.dot(base_h_tool, tool_h_cam) #print (kk) base_h_obj = np.dot(np.dot(base_h_tool, tool_h_cam), cam_h_obj) return EyeinHandResponse(base_h_obj[0, 0], base_h_obj[1, 0], base_h_obj[2, 0]) def obj_to_base_server(): rospy.init_node('eyeinhandServer') s = rospy.Service('eyeinhand', EyeinHand, tf_transform) rospy.spin() if __name__ == "__main__": obj_to_base_server()

这是一个 Python 节点，使用了 ROS 框架，提供了一个名为 'eyeinhand' 的服务。该服务的请求消息类型为 EyeinHandRequest，响应消息类型为 EyeinHandResponse。在这个节点中，定义了一个名为 tf_transform 的函数，用于处理服务的请求。这个函数接收一个请求，其中包含机器人的位姿信息和相机标定信息，并计算出相机到目标物体的位姿信息。最后，函数返回一个响应，其中包含了目标物体在机器人坐标系下的位姿信息。这个节点的主函数是 obj_to_base_server()，它初始化了 ROS 节点，并将 'eyeinhand' 服务注册到 ROS 系统中。最后，节点进入 spin() 循环，等待服务请求。

解释：target = self.survey.source.target collection = self.survey.source.collection '''Mesh''' # Conductivity in S/m (or resistivity in Ohm m) background_conductivity = 1e-6 air_conductivity = 1e-8 # Permeability in H/m background_permeability = mu_0 air_permeability = mu_0 dh = 0.1 # base cell width dom_width = 20.0 # domain width # num. base cells nbc = 2 ** int(np.round(np.log(dom_width / dh) / np.log(2.0))) # Define the base mesh h = [(dh, nbc)] mesh = TreeMesh([h, h, h], x0="CCC") # Mesh refinement near transmitters and receivers mesh = refine_tree_xyz( mesh, collection.receiver_location, octree_levels=[2, 4], method="radial", finalize=False ) # Refine core mesh region xp, yp, zp = np.meshgrid([-1.5, 1.5], [-1.5, 1.5], [-6, -4]) xyz = np.c_[mkvc(xp), mkvc(yp), mkvc(zp)] mesh = refine_tree_xyz(mesh, xyz, octree_levels=[0, 6], method="box", finalize=False) mesh.finalize() '''Maps''' # Find cells that are active in the forward modeling (cells below surface) ind_active = mesh.gridCC[:, 2] < 0 # Define mapping from model to active cells active_sigma_map = maps.InjectActiveCells(mesh, ind_active, air_conductivity) active_mu_map = maps.InjectActiveCells(mesh, ind_active, air_permeability) # Define model. Models in SimPEG are vector arrays N = int(ind_active.sum()) model = np.kron(np.ones((N, 1)), np.c_[background_conductivity, background_permeability]) ind_cylinder = self.getIndicesCylinder( [target.position[0], target.position[1], target.position[2]], target.radius, target.length, [target.pitch, target.roll], mesh.gridCC ) ind_cylinder = ind_cylinder[ind_active] model[ind_cylinder, :] = np.c_[target.conductivity, target.permeability] # Create model vector and wires model = mkvc(model) wire_map = maps.Wires(("sigma", N), ("mu", N)) # Use combo maps to map from model to mesh sigma_map = active_sigma_map * wire_map.sigma mu_map = active_mu_map * wire_map.mu '''Simulation''' simulation = fdem.simulation.Simulation3DMagneticFluxDensity( mesh, survey=self.survey.survey, sigmaMap=sigma_map, muMap=mu_map, Solver=Solver ) '''Predict''' # Compute predicted data for your model. dpred = simulation.dpred(model) dpred = dpred * 1e9 # Data are organized by frequency, transmitter location, then by receiver. # We had nFreq transmitters and each transmitter had 2 receivers (real and # imaginary component). So first we will pick out the real and imaginary # data bx_real = dpred[0: len(dpred): 6] bx_imag = dpred[1: len(dpred): 6] bx_total = np.sqrt(np.square(bx_real) + np.square(bx_imag)) by_real = dpred[2: len(dpred): 6] by_imag = dpred[3: len(dpred): 6] by_total = np.sqrt(np.square(by_real) + np.square(by_imag)) bz_real = dpred[4: len(dpred): 6] bz_imag = dpred[5: len(dpred): 6] bz_total = np.sqrt(np.square(bz_real) + np.square(bz_imag)) mag_data = np.c_[mkvc(bx_total), mkvc(by_total), mkvc(bz_total)] if collection.SNR is not None: mag_data = self.mag_data_add_noise(mag_data, collection.SNR) data = np.c_[collection.receiver_location, mag_data] # data = (data, ) return data

这段代码是一个 Python 函数，它的作用是进行三维电磁正演模拟，并返回模拟得到的数据。函数中的参数包括一个 Survey 对象和一个 Target 对象，表示要模拟的测量参数和模拟目标。函数主要分为三个部分：

1.建立网格和定义模型属性，包括电导率、磁导率和网格大小等。

2.根据接收器位置和目标位置对网格进行细化，以提高模拟精度。

3.进行电磁正演模拟，并返回模拟得到的数据。

其中，模拟的过程中还进行了噪声的添加，以模拟实际测量中的误差。