[Kbutts]

I'm trying to use the Python API to draw a visible line between a point that is at a fixed offset between the active tool's TCP and the origin of a reference frame. I can't seem to find a function that would accomplish this. Any thoughts?

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Note: The end of the line tied to the TCP should follow the tool as it moves though a simulated program.

[Albert]

I attached a sample project that shows how to draw a line between the TCP and the origin of your coordinate system (or your desired coordinates with respect to this coordinate system).

You should follow these steps to run this example:

1. Double click on ShowLine Frame2Tool to run the script
   
2. Move the robot or run a program
   

The main loop looks like this:

Code:

pose_tcp = tool.PoseTool()
pose_frame_abs = frame.PoseAbs()
pose_part_abs = part.PoseAbs()

# Calculate the inverse (invariant)
pose_part_abs_inv = pose_part_abs.inv()

# Calculate the absolute coordinate of points, then the relative coordinates
# P1 is static, it does not move
p1_abs = pose_frame_abs * frame_coords
p1_rel = pose_part_abs_inv * p1_abs

# p2 is attached to the TCP and it is moving, iteratively update p2
# p2_abs = tool.PoseAbs() * pose_tcp.Pos() # moving
p2_abs_last = p1_abs

while True:
   # Calculate p2 absolute coordinates
   p2_abs = tool.PoseAbs() * pose_tcp.Pos() # moving

   # Check if the point has changed
   if robomath.distance(p2_abs_last, p2_abs) < 0.001:
       continue

   # Calculate the distance between the 2 points
   distance = robomath.distance(p1_abs, p2_abs)
   print("Distance: %.3f mm" % distance)

   # Calculate the relative coordinates
   p2_rel = pose_part_abs_inv * p2_abs

   # Clear all object curves
   part.setParam("Reset", "Curve")

   # Add a line through 2 points
   part.AddCurve([p1_rel, p2_rel], True, robolink.PROJECTION_NONE)

   p2_abs_last = p2_abs    

[Kbutts]

That worked, thank you!

Follow up question, is there a way to adjust the line weight of a curve or set it's color via the API?

[Sam]

Yes, you can change the color of curves with the API.

You can find more information about the RoboDK Python API here:
https://robodk.com/doc/en/PythonAPI/robo...ColorCurve