include/robo_explorer_hardware.h

   1 #include <hardware_interface/joint_command_interface.h>
   2 #include <hardware_interface/joint_state_interface.h>
   3 #include <hardware_interface/robot_hw.h>
   4 #include "roboint/Inputs.h"
   5 #include "roboint/Motor.h"
   6
   7 class RoboExplorer : public hardware_interface::RobotHW
   8 {
   9         public:
  10                 RoboExplorer(ros::NodeHandle nh) {
  11                         this->nh = nh;
  12                         pub_motor = nh.advertise<roboint::Motor>("ft/set_motor", 10);
  13                         sub_inputs = nh.subscribe("ft/get_inputs", 10, &RoboExplorer::cbInputs, this);
  14
  15                         // connect and register the joint state interface
  16                         hardware_interface::JointStateHandle state_handle_left("left_wheel_joint", &pos[0], &vel[0], &eff[0]);
  17                         jnt_state_interface.registerHandle(state_handle_left);
  18                         hardware_interface::JointStateHandle state_handle_right("right_wheel_joint", &pos[1], &vel[1], &eff[1]);
  19                         jnt_state_interface.registerHandle(state_handle_right);
  20                         registerInterface(&jnt_state_interface);
  21
  22                         // connect and register the joint velocity interface
  23                         hardware_interface::JointHandle joint_handle_left(state_handle_left, &cmd[0]);
  24                         jnt_velocity_interface.registerHandle(joint_handle_left);
  25                         hardware_interface::JointHandle joint_handle_right(state_handle_right, &cmd[1]);
  26                         jnt_velocity_interface.registerHandle(joint_handle_right);
  27                         registerInterface(&jnt_velocity_interface);
  28                 }
  29
  30                 // Converts pos_encoder from wheels to wheel angles
  31                 void read(ros::Duration period) {
  32                         static double pos_last[2];
  33
  34                         pos[0] = pos_encoder[0] * M_PI/8;
  35                         pos[1] = pos_encoder[1] * M_PI/8;
  36                         vel[0] = (pos[0] - pos_last[0])/period.toSec();
  37                         vel[1] = (pos[1] - pos_last[1])/period.toSec();
  38
  39                         std::copy(std::begin(pos), std::end(pos), std::begin(pos_last));
  40                 }
  41
  42                 // Writes current velocity command to hardware
  43                 void write() {
  44                         double speed_l = 0;
  45                         double speed_r = 0;
  46                         double wish_speed_left = cmd[0];
  47                         double wish_speed_right = cmd[1];
  48                         roboint::Motor msg;
  49
  50                         if (fabs(wish_speed_left) > 0) {
  51                                 speed_l = 64.3*fabs(wish_speed_left) -1.7;
  52                                 if (wish_speed_left < 0) speed_l*=-1;
  53                         }
  54                         if (fabs(wish_speed_right) > 0) {
  55                                 speed_r = 64.3*fabs(wish_speed_right) -1.7;
  56                                 if (wish_speed_right < 0) speed_r*=-1;
  57                         }
  58
  59                         // check limits
  60                         if (speed_l < -7) speed_l = -7;
  61                         else if (speed_l > 7) speed_l = 7;
  62                         if (speed_r < -7) speed_r = -7;
  63                         else if (speed_r > 7) speed_r = 7;
  64
  65                         msg.num = 0;
  66                         msg.speed = round(speed_l);
  67                         pub_motor.publish(msg);
  68
  69                         msg.num = 1;
  70                         msg.speed = round(speed_r);
  71                         pub_motor.publish(msg);
  72                 }
  73
  74                 // Reads current input state and increases pos_encoder on change
  75                 void cbInputs(const roboint::Inputs::ConstPtr& msg) {
  76                         static std::array<uint8_t, 8> input_last;
  77
  78                         if (msg->input[0] != input_last[0]) { // left input changed
  79                                 // outputs have direction information
  80                                 if (msg->output[0] > 0) pos_encoder[0]++;
  81                                 else if (msg->output[1] > 0) pos_encoder[0]--;
  82                         }
  83                         if (msg->input[1] != input_last[1]) { // right input changed
  84                                 // outputs have direction information
  85                                 if (msg->output[2] > 0) pos_encoder[1]++;
  86                                 else if (msg->output[3] > 0) pos_encoder[1]--;
  87                         }
  88
  89                         std::copy(std::begin(msg->input), std::end(msg->input), std::begin(input_last));
  90                 }
  91
  92         private:
  93                 hardware_interface::JointStateInterface jnt_state_interface;
  94                 hardware_interface::VelocityJointInterface jnt_velocity_interface;
  95                 ros::NodeHandle nh;
  96                 ros::Publisher pub_motor;
  97                 ros::Subscriber sub_inputs;
  98                 double cmd[2];
  99                 double pos[2];
 100                 double vel[2];
 101                 double eff[2];
 102                 int64_t pos_encoder[2] = {0, 0};
 103 };