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CDRFLEx.torque_rt

Features

This is a function that controls the motor torque from an external controller.

Parameter

Parameter Name

Data Type

Default Value

Description

fMotorTor

float[6]

-

Target Motor Torque [Nm]

fTargetTime

float

-

Target Time [s]


  • Asnyc Command

  • Interpolate profile to be fMotorTor at fTargetTime.

  • If fTargetTime <= controller’s control period (=1ms), control is performed with the corresponding motor torque without interpolation.

  • If the next command is not received until arriving at fMotorTor, the last input torque is maintained.

  • However, for safety, if the next command is not received for 0.1[s], an error is generated as a time-out and stops.


In the case of the H series, there is a gravity compensator on the second axis, so the input motor torque and the torque generated by the gravitational compensator are added to move the robot. The gravity_torque of the external controller output data means (=link gravity torque – the torque of the gravity compensator)

Return

Value

Description

0

Error

1

Success

Example

C++
// main.cpp
CDRFLEx drfl;
drfl.connect_rt_control();
string version = “v1.0”;
float period = 0.001; // 1 msec
int losscount = 4;
Drfl.set_on_rt_monitoring_data(OnRTMonitoringData);
drfl.set_rt_control_output(version, period, losscount);
drfl.start_rt_control();

float time = 0.0;
int count = 0;
float q[NUMBER_OF_JOINT] = {0.0, };
float q_dot[NUMBER_OF_JOINT] = {0.0, };
float q_d[NUMBER_OF_JOINT] = {0.0, };
float q_dot_d[NUMBER_OF_JOINT] = {0.0, };
float trq_g[NUMBER_OF_JOINT] = {0.0, };
float trq_d[NUMBER_OF_JOINT] = {0.0, };
float kp[NUMBER_OF_JOINT] = {1.0, 1.0, 1.0, 1.0, 1.0, 1.0}; // have to tune
float kd[NUMBER_OF_JOINT] = {1.0, 1.0, 1.0, 1.0, 1.0, 1.0}; // have to tune
while (1)
{
    time=(++count)*period;
    // get current state
    memcpy(q, drfl.read_data_rt()->actual_joint_position, sizeof(float)*6);
    memcpy(q_dot, drfl.read_data_rt()->actual_joint_velocity, sizeof(float)*6);
    memcpy(trq_g, drfl.read_data_rt()->gravity_torque, sizeof(float)*6);

    // make trajectory
    TrajectoryGenerator(q_d, q_dot_d); // Custom Trajectory Generation Function

    // gravity compensation + pd control
    for (int i=0; i<6; i++) {
        trq_d[i] = trq_g[i] + kp[i]*(q_d[i] – q[i]) + kd[i]*(q_dot_d[i] – q_dot[i]);
    }
    drfl.torque_rt(trq_d, 0);

    if(time > plan1.time)
    {
        time=0;
        Drfl.stop(STOP_TYPE_SLOW);
        break;
    }

    rt_task_wait_period(NULL); // RTOS function
}