ROS学习:智能车室外光电组仿真

一、模型建立

首先先准备我们的开源仿真包mit-racecar，博主已经把资源上传到CSDN上了。需要请自取。
https://download.csdn.net/download/weixin_44606638/12470588
接下来将racecar_gazebo放入工作区间
编译工作区间

catkin_make

设置环境变量

echo "source ~/catkin_ws/devel/setup.bash" >> ~/.bashrc
source ~/.bashrc

这下准备就完成了，可以启动launc文件了。

roslaunch racecar_gazebo racecar.launch

注意，如果出现raise ResourceNotFound(name, ros_paths=self._ros_paths)
ResourceNotFound: racecar说明你没有racecar的模型

还是老样子，博主博主已经把资源上传到CSDN上了。需要请自取。
https://download.csdn.net/download/weixin_44606638/12470596

如果你执行成功，就会启动gazebo，就可以看见小车模型了。

二、准备赛道

目前比赛规则已经渐渐明朗，参考官方，制作标准比赛仿真环境，学习阿克曼小车控制，ROS基础和相关智能车算法（后续会补充）。开启Building Editor，依据下图绘制环境：
这时，我们在gazebo中按Ctrl+B，就会弹出绘图画面。
选择Wall，在白色区域画出你需要的赛道模型。
保存并应用：
效果展示：
当然，如果你还要添加障碍物之类的，可以在Insert中自行选择添加。这里我就不多添加了。

三、控制小车

新建文件racecar.py

Python代码：

#!/usr/bin/env python
 
"""
template_node.py
LCHS RACECAR 2016-17
Written by Braden Oh
This program serves as a template for a working node.
It contains a useful implementation of the drive function,
an outline for the main function, and contains all commands
necessary to initialize a node.  It also contains comments
outlining specific documentation.
"""
 
#----------------------------------------------------------
# IMPORTS
#----------------------------------------------------------
import rospy											# Import ROS libraries
from sensor_msgs.msg import LaserScan					# Import required msg types
from ackermann_msgs.msg import AckermannDriveStamped	
# Other imports here...
 
#----------------------------------------------------------
# CONSTANTS
#----------------------------------------------------------
DATA_IN = '/scan'									# Read data from this topic
DATA_OUT = 'vesc/ackermann_cmd_mux/input/navigation'	# Publish data to this topic
NODE_NAME = 'sampleController'						# Name of the node
SPEED = 1.0											# Default speed in m/s
# Other constants here...
 
#----------------------------------------------------------
# Functions
#----------------------------------------------------------
def drive(speed, angle, myPublisher):
        msg = AckermannDriveStamped()           # Initializes msg object
        msg.drive.speed = speed                 # Sets msg speed to entered speed
        msg.drive.acceleration = 0              # Sets msg acceleration to 0
        msg.drive.jerk = 1                      # Sets msg jerk to 1
        msg.drive.steering_angle = angle        # Sets msg steering angle to entered angle
        msg.drive.steering_angle_velocity = 1   # Sets msg angle velocity to 1
        myPublisher.publish(msg)              	# Publishes the message
        
# def myFunction(parameter_1, parameter_n):
	# Other functions here
 
#============================
# MAIN
#============================
def main(msg):
 
	# Initialize publisher object
	myPublisher = rospy.Publisher(DATA_OUT,AckermannDriveStamped,queue_size=10)
 
	# Useful calculations here...
	
	# Use the publisher
	# i.e. to drive straight ahead, call the drive function:
	# drive(SPEED, 0, myPublisher)  
 
#============================
 
rospy.init_node(NODE_NAME)					# Initialize node with preset name
rospy.Subscriber(DATA_IN,LaserScan,main)	# Create subscriber object
											#  - Reads data from preset topic
											#  - Data of type LaserScan
											#  - Upon new data, execute main
rospy.spin()	# Continue running until user stops this node
 
 

赋予可执行文件：

chmod 777 *

执行脚本：

python racecar.py

结果显示：