#!/usr/bin/env pythonimport rospyfrom mavros_msgs.msg import OverrideRCIndef set_pwm(pwm): msg = OverrideRCIn() msg.channels[8] = pwm # channel 9对应的mavros通道为8 pub.publish(msg)if __name__ == '__main__': rospy.init_node('set_pwm_node') pub = rospy.Publisher('/mavros/rc/override', OverrideRCIn, queue_size=10) rate = rospy.Rate(10) # 发布频率为10Hz while not rospy.is_shutdown(): set_pwm(1500) # 设置PWM值为1500us rate.sleep()

根据你提供的代码，可以看到这是一个Python脚本，用于控制舵机的PWM值。代码中使用了mavros的OverrideRCIn消息类型，将PWM值通过ROS的消息发布功能发送到mavros节点。

具体来说，代码中通过set_pwm函数设置舵机的PWM值，然后将PWM值发送到mavros节点，最后通过ROS消息发布器将PWM值发布出去。在while循环中，设置PWM值为1500us，即中间值，然后按照指定频率发布消息。如果你要控制舵机旋转，可以修改set_pwm函数中的PWM值，比如将PWM值设置为1000us或2000us，来控制舵机转动的方向和角度。

需要注意的是，这段代码仅供参考，具体的使用方法还需要根据实际情况进行修改和调整。另外，也需要确保舵机的连接和电源等方面的问题都已经解决。

相关问题

根据下面的Python代码编写对应的订阅这代码#!/usr/bin/env python3 #coding=utf-8 import rospy from quadrotor_msgs.msg import PositionCommand from nav_msgs.msg import Odometry from sensor_msgs.msg import Joy from mavros_msgs.msg import AttitudeTarget from tf.transformations import euler_from_quaternion import math rospy.init_node('traj_pub') local_pos_pub3 = rospy.Publisher('/position_cmd', PositionCommand, queue_size=10) poscom = PositionCommand() rate = rospy.Rate(20.0) i = 0 while not rospy.is_shutdown(): poscom.header.stamp = rospy.Time.now() poscom.header.frame_id = "world" poscom.position.x = 2.5 * math.sin(math.pi * i / 400) poscom.position.y = 5 * math.sin(math.pi * i / 800) poscom.position.z = 2 poscom.velocity.x = 0 poscom.velocity.y = 0 poscom.velocity.z = 0 poscom.acceleration.x = 0 poscom.acceleration.y = 0 poscom.acceleration.z = 0 poscom.yaw = 0 poscom.yaw_dot = 0 poscom.jerk.x = 0 poscom.jerk.y = 0 poscom.jerk.z = 0 local_pos_pub3.publish(poscom) rate.sleep() i += 1

好的，根据您的要求，以下是一段Python代码，用于订阅quadrotor机器人的Odometry话题和Joy话题：

import rospy
from nav_msgs.msg import Odometry
from sensor_msgs.msg import Joy

# 回调函数，接收到Odometry消息时调用
def odom_callback(data):
    # 处理Odometry消息
    pass

# 回调函数，接收到Joy消息时调用
def joy_callback(data):
    # 处理Joy消息
    pass

# 初始化ROS节点
rospy.init_node('my_subscriber')

# 创建一个订阅者，订阅Odometry话题
odom_subscriber = rospy.Subscriber('/odom', Odometry, odom_callback)

# 创建一个订阅者，订阅Joy话题
joy_subscriber = rospy.Subscriber('/joy', Joy, joy_callback)

# 持续监听消息
rospy.spin()

在上面的代码中，我们使用了ROS中的rospy库来连接到ROS节点，并创建了两个订阅者，分别订阅了"/odom"和"/joy"话题。当接收到来自这两个话题的消息时，我们通过回调函数odom_callback和joy_callback来处理消息。最后，我们使用rospy.spin()来持续监听消息。

更正这个Python代码使他可以在ros20.04里面发布消息#!/usr/bin/env python3 #coding=utf-8 import rospy import rospkg from quadrotor_msgs.msg import PositionCommand from nav_msgs.msg import Odometry from sensor_msgs.msg import Joy from mavros_msgs.msg import AttitudeTarget from tf.transformations import euler_from_quaternion import math rospy.init_node('traj_pub') local_pos_pub3 = rospy.Publisher('/position_cmd', PositionCommand, queue_size=10) poscom = PositionCommand() rate = rospy.Rate(20.0) i = 0 while not rospy.is_shutdown(): poscom.position.x = 2.5 * math.sin(math.pi * i / 400) poscom.position.y = 5 * math.sin(math.pi * i / 800) poscom.position.z = 2 poscom.velocity.x = 0 poscom.velocity.y = 0 poscom.velocity.z = 0 poscom.acceleration.x = 0 poscom.acceleration.y = 0 poscom.acceleration.z = 0 poscom.yaw = 0 poscom.jerk.x = 0 poscom.jerk.y = 0 poscom.jerk.z = 0 local_pos_pub3.publish(poscom) # Uncomment the following code to publish attitude target message # msg = AttitudeTarget() # q = tf.transformations.quaternion_from_euler(0, 0, 0.5) # msg.type_mask = msg.IGNORE_ROLL_RATE | msg.IGNORE_PITCH_RATE | msg.IGNORE_YAW_RATE # msg.orientation.x = q[0] # msg.orientation.y = q[1] # msg.orientation.z = q[2] # msg.orientation.w = q[3] # msg.thrust = 0.75 # local_pos_pub3.publish(msg) rate.sleep() i += 1

此代码需要在ROS环境下运行，并且需要安装以下依赖项：

1. quadrotor_msgs
2. nav_msgs
3. sensor_msgs
4. mavros_msgs

您可以通过以下命令安装这些依赖项：

sudo apt-get install ros-<distro>-quadrotor-msgs
sudo apt-get install ros-<distro>-nav-msgs
sudo apt-get install ros-<distro>-sensor-msgs
sudo apt-get install ros-<distro>-mavros-msgs

在安装完依赖项后，您可以尝试以下更改以使其在ROS 20.04中运行：

#!/usr/bin/env python3
#coding=utf-8

import rospy
from quadrotor_msgs.msg import PositionCommand
from nav_msgs.msg import Odometry
from sensor_msgs.msg import Joy
from mavros_msgs.msg import AttitudeTarget
from tf.transformations import euler_from_quaternion
import math

rospy.init_node('traj_pub')
local_pos_pub3 = rospy.Publisher('/position_cmd', PositionCommand, queue_size=10)
poscom = PositionCommand()
rate = rospy.Rate(20.0)
i = 0

while not rospy.is_shutdown():
    poscom.header.stamp = rospy.Time.now()
    poscom.header.frame_id = "world"
    poscom.position.x = 2.5 * math.sin(math.pi * i / 400)
    poscom.position.y = 5 * math.sin(math.pi * i / 800)
    poscom.position.z = 2
    poscom.velocity.x = 0
    poscom.velocity.y = 0
    poscom.velocity.z = 0
    poscom.acceleration.x = 0
    poscom.acceleration.y = 0
    poscom.acceleration.z = 0
    poscom.yaw = 0
    poscom.yaw_dot = 0
    poscom.jerk.x = 0
    poscom.jerk.y = 0
    poscom.jerk.z = 0
    local_pos_pub3.publish(poscom)
    rate.sleep()
    i += 1

此代码将发布一个有关位置命令的ROS消息，并使用ROS标准时间戳。如果您想要发布姿态目标消息，您可以取消代码中的注释并使用正确的消息类型和参数。