ros之真实驱动diy6自由度机械臂（moveit中controller源码）_moveit智能机械臂六自由度手臂

书接上回，

moveit 控制真实机器手臂时需要自己编写 控制器，控制器要有一个action server来接收 moveit的路径消息，然后控制器把消息下发到硬件上。

moveit 需要控制器获取并发布机机器手臂的状态。

此处创建两个节点，来实现这些功能。

第一个节点jointcontroller

1、负责 action server 功能，

2、路径消息转换成电机Id +角度r的一个新消息(joint_msg)，并发布/arm_motors的话题.

3、由于是舵机，并不能获取其位姿，获取部分省略。

4、发布舵机的当前位姿，即 从接收的路径消息来转换成joint_state消息，并发布/move_group/fake_controller_joint_states的话题。

第二个节点jointserial

接收话题/arm_motors，解析joint_msg 通过自定义协议串口下发。

自定义消息

joint_msg

int32 id
float64 r

jointcontroller.cpp

#include <ros/ros.h>
#include <actionlib/server/simple_action_server.h>
#include <control_msgs/FollowJointTrajectoryAction.h>
#include <trajectory_msgs/JointTrajectory.h>
#include <std_msgs/Float64.h>
#include <iostream>
#include <vector>
#include <string>
#include <sensor_msgs/JointState.h>
#include <map>
#include "zzz_arm_control_driver/joint_msg.h"
 
using namespace std ;
typedef actionlib::SimpleActionServer<control_msgs::FollowJointTrajectoryAction> Server;
 
class RobotTrajectoryFollower
{
protected:
 
  ros::NodeHandle nh_;
  // NodeHandle instance must be created before this line. Otherwise strange error may occur.
  //actionlib::SimpleActionServer<control_msgs::FollowJointTrajectoryAction> as_;
  std::string action_name_;
 
  ros::Publisher joint_pub ;
  ros::Publisher joint_motor_pub ;
  sensor_msgs::JointState joint_state;
  zzz_arm_control_driver::joint_msg joint_motor_msg;
 
  control_msgs::FollowJointTrajectoryResult result_;
  control_msgs::FollowJointTrajectoryActionGoal agoal_;
  control_msgs::FollowJointTrajectoryActionFeedback afeedback_;
  control_msgs::FollowJointTrajectoryFeedback feedback_;
public:
  map< string, int > MotoName_Id;
  RobotTrajectoryFollower(std::string name) :
    nh_("~"),
    as_(nh_, name,boost::bind(&RobotTrajectoryFollower::goalCB, this, _1),  false),
    action_name_(name)
  {
    /*<!--
    shoulder_wan_joint:1
    upper_arm_joint:2
    middle_arm_joint:3
    fore_arm_joint:4
    tool_joint:5 -->*/
    nh_.param("shoulder_wan_joint", MotoName_Id["shoulder_wan_joint"], 0);
    nh_.param("upper_arm_joint", MotoName_Id["upper_arm_joint"], 0);
    nh_.param("middle_arm_joint", MotoName_Id["middle_arm_joint"], 0);
    nh_.param("fore_arm_joint", MotoName_Id["fore_arm_joint"], 0);
    nh_.param("tool_joint", MotoName_Id["tool_joint"], 10);
 
    joint_pub = nh_.advertise<sensor_msgs::JointState>("/move_group/fake_controller_joint_states", 1);
 
    joint_motor_pub = nh_.advertise<zzz_arm_control_driver::joint_msg>("/arm_motors", 1000);
 
    //Register callback functions:
    //as_.registerGoalCallback(boost::bind(&RobotTrajectoryFollower::goalCB, this,_1));
    as_.registerPreemptCallback(boost::bind(&RobotTrajectoryFollower::preemptCB, this));
 
    as_.start();
  }
 
  ~RobotTrajectoryFollower(void)//Destructor
  {
  }
//
  void setJointStateName(std::vector<std::string> joint_names){
    joint_state.name.resize(joint_names.size());
    joint_state.name.assign(joint_names.begin(), joint_names.end());
    //joint_state.name[0] ="arm_1_to_arm_base";
    //std::vector<std::string>::iterator it;
    //for ( it = joint_state.name.begin(); it != joint_state.name.end(); it++){
    //  cout <<(*it) <<endl;
    //}
    //cout <<endl ;
  }
  void setJointStatePosition(std::vector<double> joint_posi){
    joint_state.position.resize(joint_posi.size());
    joint_state.position.assign(joint_posi.begin(), joint_posi.end());
    //joint_state.position[0] = base_arm;
    //std::vector<double>::iterator it;
    //for ( it = joint_state.position.begin(); it != joint_state.position.end(); it++){
    //  cout <<(*it) <<endl;
    //}
    //cout <<endl ;
  }
  void publishJointState(){
    joint_state.header.stamp = ros::Time::now();
    joint_pub.publish(joint_state);
  }
  void publishMotorState(int ids[],std::vector<double> joint_posi){
 
 
    std::vector<double>::iterator it;
    int i=0;
    for ( it = joint_posi.begin(); it != joint_posi.end(); it++,i++){
      joint_motor_msg.id=ids[i];
      joint_motor_msg.r=(*it) ;
      joint_motor_pub.publish(joint_motor_msg);
      cout <<joint_motor_msg <<endl;
 
    }
 
 
  }
  void goalCB(const control_msgs::FollowJointTrajectoryGoalConstPtr msg)
  {
    //cout<<((*msg))<<endl;
    std::vector<std::string> joint_names=(*msg).trajectory.joint_names;
    //
    setJointStateName( joint_names);
 
    std::vector<std::string>::iterator it;
    int ids [joint_names.size()];
    int i=0;
    for ( it = joint_names.begin(); it != joint_names.end(); it++,i++){
      ids[i]=MotoName_Id[(*it)];
      cout <<MotoName_Id[(*it)] <<endl;
    }
 
    //goal=(*msg);goal.trajectory.points;//c++ how to use this style??
 
    std::vector<trajectory_msgs::JointTrajectoryPoint> points = (*msg).trajectory.points;
    std::vector<trajectory_msgs::JointTrajectoryPoint>::iterator pointsit;
    ros::Rate rate(10);//10hz
    size_t t=points.size();
    ROS_INFO("%s: goalCB ", action_name_.c_str());
    for ( pointsit = points.begin(); pointsit != points.end(); pointsit++){
      //cout<<(*pointsit)<<endl;
      //cout <<endl ;
      //here send datamsg to hardware node,command motors run.
      //
      publishMotorState(ids,(*pointsit).positions);
      //wait
      rate.sleep();
      //then update joinstates an publish
      setJointStatePosition((*pointsit).positions);
      publishJointState();
      //feedback_.
      //as_.publishFeedback(feedback_);
      ROS_INFO("left position :%d", (int)t);
      t--;
    }
 
    // accept the new goal
    //as_.acceptNewGoal();
    if(as_.isActive())as_.setSucceeded();
  }
 
  void preemptCB()
  {
    ROS_INFO("%s: Preempted", action_name_.c_str());
    // set the action state to preempted
 
    if(as_.isActive()){
        as_.setPreempted();
    }
  }
  Server as_;
};
 
int main(int argc, char** argv)
{
 
  ros::init(argc, argv, "jointcontroller");
  RobotTrajectoryFollower RobotTrajectoryFollower("/zzz_arm_controller/follow_joint_trajectory");
 
;
  ROS_INFO("-------------zzz joint controller is running .");
  ros::spin();
 
  return 0;
}
 

jointserial.cpp

#include <ros/ros.h>
#include <serial/serial.h>
//ROS已经内置了的串口包
#include <std_msgs/String.h>
#include <std_msgs/Empty.h>
#include "zzz_arm_control_driver/joint_msg.h"
#include <boost/asio.hpp>                  //包含boost库函数
 
 
using namespace boost::asio;           //定义一个命名空间，用于后面的读写操作
using namespace std;
serial::Serial ser; //声明串口对象
//io_service Object
io_service m_ios;
 
//Serial port Object
serial_port *pSerialPort;
 
//For save com name
//any_type m_port;
 
//Serial_port function exception
boost::system::error_code ec;
 
 
std::string serial_port_name;
int serial_baudrate = 115200;
unsigned char AA=1;
unsigned char aa;
//回调函数
void write_callback(const zzz_arm_control_driver::joint_msg::ConstPtr& msg)
{
    ROS_INFO_STREAM("Writing to serial port" <<msg->id<<msg->r);
    unsigned char mid=(char) msg->id;
    double r=msg->r;
    if(mid==1){
      r+=3.1415926536/4.0;//motor1 limit:-45~45
    }
    r=r<0.0?0.0:r;
    r=r>3.1415926/2.0?3.1415926/2.0:r;
    double per=r/(3.1415926/2.0);
 
    per=(mid==1||mid==5)?per:(1-per);
    unsigned short  mr=(unsigned short )((per)*1024.0);
 
    ROS_INFO("id:%d per:%d",mid,mr);
    unsigned char* mrp=  (unsigned char*)&mr;
 
    unsigned char b1,b2,b3;
    //11aa aaAA
    b1=0xc0|(mid<<2);
    b1|=0x03&(AA>>2);
    //10AA xxxx
    b2=0x80|(AA<<4);
    b2|=(0x0c&((*(mrp+1))<<2))|(0x03&((*(mrp))>>6));
    //01xx xxxx
 
    b3=0x40|(0x3f&(*(mrp)));
    char cdata[3];
    cdata[0]=b1;
    cdata[1]=b2;
    cdata[2]=b3;
    string data="";
    data+=b1;
    data+=b2;
    data+=b3;
 
    //ser.write(data);//发送串口数据
    try
    {
      size_t len = write( *pSerialPort, buffer( cdata,3 ), ec );
    }catch (boost::system::system_error e){
        ROS_ERROR_STREAM("serail write err ");
 
    }
}
 
int main (int argc, char** argv)
{
 
    //初始化节点
    ros::init(argc, argv, "jointserial");
    //声明节点句柄
    ros::NodeHandle nh;
 
    //订阅主题，并配置回调函数
    ros::Subscriber write_sub = nh.subscribe("/arm_motors", 1000, write_callback);
    //发布主题
    //ros::Publisher read_pub = nh.advertise<std_msgs::String>("read", 1000);
    ros::NodeHandle nh_private("~");
    nh_private.param<std::string>("serial_port", serial_port_name, "/dev/ttyUSB0");
    nh_private.param<int>("serial_baudrate", serial_baudrate, 115200);
 
    /*try
    {
    //设置串口属性，并打开串口
      ROS_INFO("%s",serial_port_name.c_str());
      ser.setPort(serial_port_name);
      ser.setBaudrate(serial_baudrate);
      serial::Timeout to = serial::Timeout::simpleTimeout(10000);
      ser.setTimeout(to);
      ser.open();
    }
    catch (serial::IOException& e)
    {
        ROS_ERROR_STREAM("Unable to open port ");
        return -1;
    }
    //检测串口是否已经打开，并给出提示信息
    if(ser.isOpen())
    {
        ROS_INFO_STREAM("Serial Port initialized");
    }
    else
    {
        return -1;
    }//*/
    pSerialPort = new serial_port( m_ios );
    if ( pSerialPort ){
        //init_port( port_name, 8 );
        //Open Serial port object
        pSerialPort->open( serial_port_name, ec );
        //Set port argument
        pSerialPort->set_option( serial_port::baud_rate( serial_baudrate ), ec );
        pSerialPort->set_option( serial_port::flow_control( serial_port::flow_control::none ), ec );
        pSerialPort->set_option( serial_port::parity( serial_port::parity::none ), ec );
        pSerialPort->set_option( serial_port::stop_bits( serial_port::stop_bits::one ), ec);
        pSerialPort->set_option( serial_port::character_size( 8 ), ec);
        m_ios.run();
    }
 
    short int a = 0x1234;
    char *p = (char *)&a;
 
    ROS_INFO("p=%#hhx\n", *p);
 
    if (*p == 0x34) {
        ROS_INFO("little endian\n");
    } else if (*p == 0x12) {
        ROS_INFO("big endia\n");
    } else {
        ROS_INFO("unknown endia\n");
    }
 
    ROS_INFO("-------------zzz joint serail is running .");
    ros::spin();
 
    return 0;
 
/*
    //指定循环的频率
    ros::Rate loop_rate(50);
    while(ros::ok())
    {
        if(ser.available()){
            ROS_INFO_STREAM("Reading from serial port\n");
            std_msgs::String result;
            result.data = ser.read(ser.available());
            ROS_INFO_STREAM("Read: " << result.data);
            read_pub.publish(result);
        }
        //处理ROS的信息，比如订阅消息,并调用回调函数
        ros::spinOnce();
        loop_rate.sleep();
    }*/
}