check_position_condition (Manual Mode)

This section explains how to use check_position_condition during Manual (Teach) operations to evaluate whether the position of a specified axis meets a defined range condition relative to a target position.

This function allows users to implement conditional position checks within teaching routines to verify alignment, approach distance, or safety constraints before executing the next motion.

Typical usage

• Verify whether the robot’s TCP has reached a specific position range before triggering the next step.

• Monitor relative or absolute position offsets for approach validation or contact detection.

• Use within while or if statements to create looped condition checks during teaching.

• Switch between absolute (global) and relative (offset) comparisons using eMode:
  - MOVE_MODE_ABSOLUTE: compare absolute position within workspace.
  - MOVE_MODE_RELATIVE: compare deviation from target pose.
  

Note

• This function performs read-only monitoring and does not initiate motion.

Example: Position Range Check in Manual Teaching

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

int main() {
    CDRFLEx drfl;

    // Preconditions:
    // - Robot connected and servo ON
    // - Manual (Teach) mode active
    // - Robot is near target pose

    // 1) Define a target pose (reference for comparison)
    float targetPose[6] = {400.f, 500.f, 600.f, 0.f, 180.f, 0.f};

    // 2) Check relative Z-axis offset (±5 mm tolerance)
    bool relCond = drfl.check_position_condition(FORCE_AXIS_Z, -5.f, 5.f, targetPose, MOVE_MODE_RELATIVE);

    // 3) Check absolute X-axis position (workspace limit)
    bool absCond = drfl.check_position_condition(FORCE_AXIS_X, 100.f, 200.f, targetPose, MOVE_MODE_ABSOLUTE, COORDINATE_SYSTEM_BASE);

    if (relCond)
        printf("Relative condition met: TCP Z within ±5 mm of target.\n");
    else
        printf("Relative condition not met.\n");

    if (absCond)
        printf("Absolute condition met: X-axis between 100–200 mm.\n");
    else
        printf("Absolute condition not met.\n");

    // 4) Example: loop until relative condition is satisfied
    while (!relCond) {
        relCond = drfl.check_position_condition(FORCE_AXIS_Z, -5.f, 5.f, targetPose, MOVE_MODE_RELATIVE);
        std::this_thread::sleep_for(std::chrono::milliseconds(200));
    }

    printf("Target range reached — ready for next task.\n");
    return 0;
}

In this example, the function is used to check whether the robot’s TCP position satisfies both relative and absolute positional constraints before proceeding. It can be used to monitor teaching accuracy, approach distance, or safety compliance during manual motion control or calibration.

Tips

• Use MOVE_MODE_ABSOLUTE for verifying workspace boundaries, teaching points, or safe zones.

• Use MOVE_MODE_RELATIVE for approach or alignment tasks where deviation from a reference is critical.

• Combine with check_force_condition to create force-position hybrid logic during contact or assembly teaching.

• For smoother monitoring, call this function periodically (every 50–200 ms).

• Always ensure consistency between fTargetPos coordinates and the chosen reference frame (BASE or TOOL).