Lesson 9 of 10 · 7 min
When the robot perceives and speaks
A robot that follows a rule is programmed. A robot that recognises a gesture or converses through a language model has been trained. The difference can be understood in class.
When Thymio avoids an obstacle, it applies a rule someone wrote: if the front sensor sees a nearby object, turn. You can read the rule, predict the behaviour and correct the program. A robot that recognises a gesture or an image works differently. Nobody wrote the rule. A model learned it from examples. It succeeds on cases close to its examples and can get the others wrong.
The micro:bit lets you bring this to life in class. The free micro:bit CreateAI tool records gestures with the motion sensor of the V2 board, trains a model, lets you test it, then sends it into a MakeCode program on the board. Students see that with few examples, or with gestures that are too similar, the model gets confused.
Robots and toys now hold conversations thanks to a language model. Their answers are fluent, but they can be wrong, and the same message does not always get the same answer. When the model runs on a server, the child’s voice is sent there to be transcribed and processed. The review by Belpaeme and colleagues, in 2018, already noted that understanding young children’s speech remained difficult for robots.
- Programming a rule: Thymio follows a line or avoids an obstacle. The students write the rule in plain English.
- Training a model: with CreateAI, three gestures, a few examples of each, then a test by another student.
- Comparing: who decided the behaviour? Why does it get things wrong? What has to change to correct it, the program or the examples?
References
- Belpaeme, Kennedy, Ramachandran et al. (2018). Social robots for education: A review. Science Robotics 3(21), eaat5954. doi.org/10.1126/scirobotics.aat5954