EV3 Phi. Teacher Note. Add a touch sensor without instructions Pro Preview

What is allowed and what is not when building without instructions.

  • #432
  • 03 May 2017
  • 2:59

Use beams

Students tend to use axles when they build. Show them an alternative, show them how to build with beams.

Positioning of the sensor

Let the students build any way the like. The sensor may be placed anywhere on the robot, as long as it is pointing forward and it is outside of the frame of the robot.


A few notes for the teacher on how based on our experience of course most of the students will add this sensor to the front of the robot. Few things to note here. First, when they have this task most of the students will try to extend the construction with axles either with a gray one or a black one because it's easy to do this with an axle but a more durable way is to use beams. Don't stop them but just have in mind that the students that are starting with an axle will probably at the end have a construction not that durable or it will take them more time to add the touch sensor to the front of the robot. The other thing is that you can add the sensors at different places at the front of the robot. You can even for the next few sessions, for the next few videos you can even add the sensor at the top of the robot. Now, it's preferable if you don't stop the students if the decide to add the sensor at a different position even on the top of the robot. Why? Because that's a part of their imagination and they'll try, they'll come up with different solutions and it's interesting then to discuss this solution. But as a general rule the touch sensor should not be inside the frame of the robot because the idea of the touch sensor is that when you move it can actually touch things at the front. And if the sensor is inside the frame of the robot, it will be the robot first bumping at the wall and the sensor will not be able to bump. If of course you do not extend the sensor but that's a topic for some of the next videos. Probably the most difficult thing that the student will have to solve now, the most difficult task is how to change the direction of the holes of the different beams. So, in this case you can think of the beam as facing up and how do you using some of the parts in the set change this direction with a couple of other beams so that at the end it will face left or right. So, it's horizontal instead of vertical. And this will be something difficult for most of the students but at the end in about 10-15 minutes probably they'll come up with a solution. If you have a student that have accomplished this in a very short time, you can give them a more complex task to make this longer or to make this higher so that they could keep up with the rest of the group.