ros之真实驱动diy6自由度机械臂（moveit中controller源码）

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
c61a
;
}
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();

}*/
}