set_workpiece_weight (Auto Mode)

This section explains how to use set_workpiece_weight during Auto (Run) operations to configure the active workpiece weight and optional center of gravity (CoG) information. Accurate payload configuration is essential for stable trajectory planning, force control performance, and safe execution of automated tasks.

This function is typically called before starting automated cycles such as pick & place, palletizing, or contact-based assembly operations.

Typical usage

  • Register the mass of the part currently held by the gripper.

  • Update payload when switching products or workpiece types.

  • Adjust robot dynamics and force control behavior for varying weights.

  • Ensure correct torque estimation before executing high-speed Auto Mode motions.

Note

  • fWeight is expressed in kilograms (kg).

  • fCog represents the CoG offset relative to the TCP or flange frame.

  • If using Smart Setup, measured workpiece values can be applied directly here.

  • Incorrect payload settings may lead to unstable force control or safety stops.

Example: Setting Workpiece Payload Before Auto Cycle

#include "DRFLEx.h"
#include <cstdio>
using namespace DRAFramework;

int main() {
    CDRFLEx drfl;

    // Example: 2.5 kg part with CoG offset in Z direction
    float cog[3] = {0.0f, 0.0f, 50.0f};  // 50 mm above TCP

    // Configure workpiece weight
    if (!drfl.set_workpiece_weight(2.5f, cog)) {
        printf("Failed to set workpiece weight.\n");
        return -1;
    }

    // Perform Auto Mode motion with updated payload
    float target[6] = {400.f, 150.f, 280.f, 180.f, 0.f, 0.f};
    drfl.movej(target, 60.f, 30.f);

    return 0;
}

In this example, the workpiece weight and CoG are configured prior to running automated movements. This ensures that the robot uses correct payload parameters for stable and safe Auto Mode execution.

Tips

  • Call this function whenever a new part is picked up.

  • Use precise values (Smart Setup recommended) for best force/compliance performance.

  • Revert to empty-gripper payload with reset_workpiece_weight after dropping the part.

  • Avoid rapidly switching payload values while the robot is moving.