n_private.param("walk_vel", walk_vel_, 0.2)
时间: 2024-04-04 10:35:18 浏览: 49
`n_private.param("walk_vel", walk_vel_, 0.2)`是ROS中一个参数服务器的命令,用于从ROS参数服务器中获取参数值。在这个命令中,“walk_vel”是参数名称,它指定了要获取的参数。`walk_vel_`是一个变量,用于存储获取到的`walk_vel`参数值。`0.2`是在参数服务器上找不到`walk_vel`参数时的默认值。
这个命令通常在ROS节点的构造函数中使用。它可以从ROS参数服务器中获取节点的运行参数,以便在程序运行时使用。这种方法可以使得节点的参数值可以在启动节点时通过ROS launch文件进行设置。
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给下列程序添加注释: void DWAPlannerROS::reconfigureCB(DWAPlannerConfig &config, uint32_t level) { if (setup_ && config.restore_defaults) { config = default_config_; config.restore_defaults = false; } if ( ! setup_) { default_config_ = config; setup_ = true; } // update generic local planner params base_local_planner::LocalPlannerLimits limits; limits.max_vel_trans = config.max_vel_trans; limits.min_vel_trans = config.min_vel_trans; limits.max_vel_x = config.max_vel_x; limits.min_vel_x = config.min_vel_x; limits.max_vel_y = config.max_vel_y; limits.min_vel_y = config.min_vel_y; limits.max_vel_theta = config.max_vel_theta; limits.min_vel_theta = config.min_vel_theta; limits.acc_lim_x = config.acc_lim_x; limits.acc_lim_y = config.acc_lim_y; limits.acc_lim_theta = config.acc_lim_theta; limits.acc_lim_trans = config.acc_lim_trans; limits.xy_goal_tolerance = config.xy_goal_tolerance; limits.yaw_goal_tolerance = config.yaw_goal_tolerance; limits.prune_plan = config.prune_plan; limits.trans_stopped_vel = config.trans_stopped_vel; limits.theta_stopped_vel = config.theta_stopped_vel; planner_util_.reconfigureCB(limits, config.restore_defaults); // update dwa specific configuration dp_->reconfigure(config); }
/**
* @brief Callback function for dynamic reconfiguration of DWA planner parameters
*
* @param config Reference to the configuration object that stores the updated parameters
* @param level The level of reconfiguration, unused in this function
*/
void DWAPlannerROS::reconfigureCB(DWAPlannerConfig &config, uint32_t level) {
// If the setup has been completed and restore_defaults flag is set, restore default configuration
if (setup_ && config.restore_defaults) {
config = default_config_;
config.restore_defaults = false;
}
// If setup has not been completed, store default configuration and set the setup flag to true
if ( ! setup_) {
default_config_ = config;
setup_ = true;
}
// Update generic local planner parameters
base_local_planner::LocalPlannerLimits limits;
limits.max_vel_trans = config.max_vel_trans;
limits.min_vel_trans = config.min_vel_trans;
limits.max_vel_x = config.max_vel_x;
limits.min_vel_x = config.min_vel_x;
limits.max_vel_y = config.max_vel_y;
limits.min_vel_y = config.min_vel_y;
limits.max_vel_theta = config.max_vel_theta;
limits.min_vel_theta = config.min_vel_theta;
limits.acc_lim_x = config.acc_lim_x;
limits.acc_lim_y = config.acc_lim_y;
limits.acc_lim_theta = config.acc_lim_theta;
limits.acc_lim_trans = config.acc_lim_trans;
limits.xy_goal_tolerance = config.xy_goal_tolerance;
limits.yaw_goal_tolerance = config.yaw_goal_tolerance;
limits.prune_plan = config.prune_plan;
limits.trans_stopped_vel = config.trans_stopped_vel;
limits.theta_stopped_vel = config.theta_stopped_vel;
// Call reconfigureCB function of the planner_util_ object with updated limits and restore_defaults flag
planner_util_.reconfigureCB(limits, config.restore_defaults);
// Call reconfigure function of the dp_ object with updated configuration
dp_->reconfigure(config);
}
if __name__=='__main__': rospy.init_node('encoder_vel', log_level=rospy.DEBUG) pub = rospy.Publisher('encoder', Odometry, queue_size=10) port = rospy.get_param('~serial_port', '/dev/encoder') baud = rospy.get_param('~baud_rate', 57600) # about 100hz k = rospy.get_param('~k',1) # fix param ser = serial.Serial(port, baud) print(ser.is_open) while( not rospy.is_shutdown()): # time1 = time.time() send_data = bytes.fromhex('01 03 00 03 00 01 74 0A') # read velocity value in 20ms ser.write(send_data) datahex = ser.read(7) angle_v = DueVelData(datahex) send_data = bytes.fromhex('01 03 00 00 00 01 84 0A') # ser.write(send_data) datahex = ser.read(7) dir = DueDirData(datahex) Vel = angle_v * dir * C / 1024.0 / 0.02 * k # print(Vel) # time2 = time.time() # print(1/(time2-time1)) pub_vel = Odometry() pub_vel.header.frame_id = 'odom' pub_vel.child_frame_id = 'base_footprint' pub_vel.header.stamp = rospy.Time.now() pub_vel.twist.twist.linear.x = Vel pub.publish(pub_vel)
这段代码是一个Python程序的主函数,它首先通过调用rospy.init_node()函数初始化ROS节点,并创建一个名为'encoder_vel'的节点。接着,它使用rospy.Publisher()函数创建一个名为'encoder'的消息发布者,用于发布Odometry类型的消息。这个消息发布者的队列长度为10。
接下来,程序通过调用rospy.get_param()函数获取程序的运行参数,包括串口的名称、波特率和一个名为k的系数参数。然后,程序使用Python内置的serial.Serial()函数创建一个串口对象,并打开该串口。
在主循环中,程序首先发送一个读取速度值的命令(send_data),并从串口读取返回的数据(datahex)。然后,程序调用DueVelData()函数将读取到的数据解析成角度值(angle_v)。接着,程序发送一个读取方向值的命令(send_data),并从串口读取返回的数据(datahex)。然后,程序调用一个名为DueDirData()的函数将读取到的数据解析成方向值(dir)。最后,程序根据角度值和方向值计算并发布速度值(Vel)。
需要注意的是,程序使用了一个名为rospy.is_shutdown()的函数来检查ROS节点是否已经被关闭,如果节点已经被关闭,则退出程序。程序还使用了一个名为rospy.Time.now()的函数来获取当前时间,并将这个时间赋值给Odometry消息的时间戳。
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