Features and Safety Planes

Theme

  1. Define features and safety plane

  2. Define TCP

  3. for and if loop

  4. Fill and empty ball dispensers

Equipment

  1. UR5 / UR5e robot with PolyScope (they are different, old/new).

  2. Robotiq 2-Finger Adaptive Robot Gripper / Hand-E Gripper

  3. Lab station with two ball dispensers and 4 balls.

Before the lab

  1. Complete the Universal Robots Academy *<– this is very important!*

    • “3. Setting up a tool”

    • “7. Safety settings”

    • “9. Program Flow”

    • “10. Feature Coordinates”

  2. Try to get together in a group of 2-4 people.

Report

There is no need to hand in a report after this lab.

Signed attendance will suffice as approved lab exercise.

Tasks

  1. Set up a tool.

  2. Define a safety plane.

  3. Define a safety ball around the tool.

Infinite ball pick and place

../_images/lab2_pic.png

Initial conditions: Left (1) ball dispenser has 4 balls, right (2) ball dispenser has 0 balls.

In this task you will program the robot to move one ping-pong ball at a time

The program flow is the following

  1. Pick ball from 1. dispenser

    • if ball not detected, halt

  2. Place it in 2. dispenser

  3. Repeat step 1-2 4 times

  4. Pick balls from 2. dispenser

    • if ball not detected, halt

  5. Place balls in 1. dispenser

  6. Repeat step 4-5 4 times

  7. Loop for ever

The dispensers will be moved around when you’re done. Therefore, make features for each dispenser and define waypoint like “approach dispenser 1” relative to dispenser 1’s feature with an origo that makes sense. For more accuracy, consider using a reference when defining a feature.

Test that balls are picked for ever. Move dispensers, update their features, test that stuff still work.

Questions

  1. How will moveL motions differ if relative to your TCP, and if relative to flange?

  2. What will happen if tool weight is entered too high or too low, and when?

  3. Which direction does your TCP Z-axis point?

  4. What did you use the safety plane for?

  5. Did you make features for the dispensers?

  6. Did stuff work after moving the dispensers around? Why?