Coordinate Control (RobotArm)

Coordinate control means specifying the end-effector pose in the base coordinate system as [x, y, z, rx, ry, rz]: where x, y, z are positions (mm), and rx, ry, rz are orientations (°, Euler-angle semantics follow the controller implementation). This document is based on RobotArm (include/RobotArm.hpp), for MyCobotPro450, with Linux + TCP communication (see Environment Setup and Build).

All interfaces below follow the same format: Function, Return Value, Parameter Description, and Range. For the full API index, see API Reference.

Coordinate Component Ranges (MyCobotPro450)

Speed sp / speed: 1 ~ 100 (same throughout this document).

Single Axis

int sendCoord(uint8_t axis, float coord, uint8_t sp)

• Function: Sends a target coordinate/orientation value for one axis.
• Return Value: Usually 1 on success, -1 on failure.
• Parameter Description: axis is 1~6 (mapping to x, y, z, rx, ry, rz); coord is the target value; sp is speed level.
• Range: axis: 1 ~ 6; coord: see table above; sp: 1 ~ 100.

Six Axes

Coords getCoords()

• Function: Reads the current 6D pose [x, y, z, rx, ry, rz].
• Return Value: Coords (std::array<float, 6>), index 0 ~ 5 maps to axis 1 ~ 6.
• Parameter Description: None.
• Range: None.

int SendCoords(Coords coords, uint8_t sp)

• Function: Sends the full 6D pose in one command.
• Return Value: Usually 1 on success, -1 on failure.
• Parameter Description: coords six components; sp speed level.
• Range: Each component follows the axis ranges in the table above; sp: 1 ~ 100.

Coordinate JOG

int jogCoord(uint8_t axis, uint8_t direction, uint8_t speed)

• Function: Continuously moves along a specified coordinate axis in one direction until a limit is reached or stop() is called.
• Return Value: Usually 1 on success, -1 on failure.
• Parameter Description: axis; direction; speed.
• Range: axis: 1 ~ 6; direction: 0 negative, 1 positive; speed: 1 ~ 100.

In-Position Check (Coordinate Target)

int isInPosition(Angles angle_coords, bool mode)

• Function: Checks whether the end-effector has reached a given 6D target. For coordinate mode, set the second argument to true (the underlying type is still std::array<float, 6> for both Angles/Coords).
• Return Value: 1 reached; 0 not reached; -1 abnormal or no valid response.
• Parameter Description: angle_coords six target values (here representing x, y, z, rx, ry, rz); mode.
• Range: For coordinate checks, use mode == true; component ranges are shown in this chapter's coordinate table.

Motion Stop (Used with JOG, etc.)

int stop()

• Function: Stops the current motion.
• Return Value: Usually 1 on success, -1 on failure.
• Parameter Description: None.
• Range: None.

Example (Excerpt)

The example below demonstrates reading coordinates, sending a 6D pose, checking in-position status in coordinate mode, coordinate JOG, and stop. Ensure target points are within the robot workspace and the path is safe.

#include "RobotArm.hpp"
#include "config.hpp"
#include <iostream>
#include <thread>
#include <chrono>

using namespace std::chrono_literals;

int main() {
    Param p;
    p.ip_serial = "192.168.0.232";
    p.port_baud = 4500;

    RobotArm arm(TCP_COMM, p);

    if (arm.powerOn() != 1) {
        std::cerr << "powerOn failed\n";
        return 1;
    }

    Coords cur = arm.getCoords();
    std::cout << "x=" << cur[0] << " y=" << cur[1] << " z=" << cur[2] << "\n";

    Coords goal = {200.f, 100.f, 250.f, 0.f, 0.f, 0.f}; // Set target based on current real robot pose
    if (arm.SendCoords(goal, 30) != 1) {
        std::cerr << "SendCoords failed\n";
    }

    while (arm.isInPosition(goal, true) != 1) {
        cur = arm.getCoords();
        std::cout << "x=" << cur[0] << " ...\n";
        std::this_thread::sleep_for(200ms);
    }

    arm.jogCoord(1, 1, 30);
    std::this_thread::sleep_for(2s);
    arm.stop();

    arm.powerOff();
    return 0;
}

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