Exercise 11: Painting robot


The remote-controlled buggy from model 10 is converted into a painting robot.

The drawing of simple geometric figures can be automated: This requires time measurement of rotations (= angles) and straight lines (= line length).

Note: The tasks can be programmed most reliably with a USB connection to the fischertechnik BT Smart Controller, as transmission delays occur with a Bluetooth connection.


How can the buggy be turned through a specified angle? How can the buggy drive along a specified route?


Learning objective

  • Representation of angles and distances by times
  • Measuring times with Scratch

Time required

It takes about half an hour to assemble the painting robot. If the buggy from model 10 is still assembled, it can be converted and the construction time thus shortened. The first task „Control painting robot“ is a direct application of the remote control of the buggy programmed in model 10 (buggy). Task „Measuring the painting robot“ requires several measurements to determine the times required to turn through the necessary angles (120°, 90°) and to travel a certain distance. Task 3 is a direct application of the measurement results and is not difficult to program. One lesson should be sufficient to solve the tasks.

Solving the experimental task is a little trickier; it requires at least one lesson of its own. The solution can be supported by collecting interim results (such as the „painting strategy“ for the „House of Santa Claus“ or determining the required distances and angles) together.