Engineering - Remote controlling

Before building a mobile robot such as the one we build this morning, an engineer is likely to first study what controller he can pick, choose one and test it. Once this is done, he might study the available motors, choose one type of motor, and make sure he's able to control them. Only once he mastered every individual elements will he put them together. Problem decomposition is a key skill for every engineer.

In the previous activities, the problems to solve have always been decomposed in simpler problems for you to advance safely in them in a similar fashion. Indeed this is standard in pedagogy too. Therefore, you have already been exposed to this process a lot. This afternoon's goal is to make you practice doing this problem decomposition yourself.

What you will need

The material is the same as this morning's material, except for the cardboard which is not needed. However , as we'll make two micro:bits interact, you will have to be at least two pairs (with one micro:bit each) and to organise yourselves among pairs.

Remote controlled buggy

Figure: Radio controlled Buggy

The problem you will practice your problem decomposition skill on will consist in programming a remote controlled buggy: the remote control (or joystick) will be a micro:bit, which will send its commands to the buggy through radio waves: tilt the joystick forward and the buggy moves forward, tilt the joystick left and the buggy turns left...

Exercise

Define the milestones that you and your team will have to reach to eventually have the whole problem solved. In other words, find many smaller problems to solve that will help you solve the bigger problem at hand. As you will need to have two micro:bit to do your experiments, your team will have to be composed of at least two pairs of learners. The documentation of the radio emitter and receptor of the micro:bit can be found here.

Solution

After some time, we will provide you with a proposition of milestones.

More projects

If you managed to program the micro:bit as asked in the previous project, here are some more ideas you can work on to develop your engineering skills:

  • Project 1 (incremental): Control the buggy using another micro:bit equipped with two potentiometers (remove the batteries if you do so to make sure you don't give 5V to micro:bit and burn it). One potentiometer for the forward/backward speed, the other for turning (like on many RC vehicles)

  • Project 2 (hard): Program the buggy to always come back to the orientation it started with. For this you'll need to use it's internal compas which is quite a special sensor.

Conclusion

This afternoon you focused on problem decomposition. This strategy is not only useful in engineering but in many, many other fields. As a sportsman, if you want to learn a new move, if you have the chance to have a coach, he will help you break down this new move in simpler moves. If you don't have a coach then you will increase you chances to do the move right in decomposing it in simpler movements and pratice them individually. As a musician, before learning to play a tune, you will benefit in learning to play scales beforehand, as boring as it might seem.

While it is easy to disregard such practices as boring, we should not forget their power: the smaller problems we solved or the simple skills we develop are often at the fundation of many other bigger problems or skills. Once we mastered one scale, it is not one tune that we can play with more ease but all the other tunes in this scale. And the same applies for problem solving in engineering.