Lesson 02 · 60 minutes
Driving & the Remote
Commands, control, and who is in charge
Today's goal
Drive the robot three different ways and explain what a command actually is.
Ideas in this lesson
- A command is a message, not a wish — something has to receive it
- Two controllers, one robot: first one to act owns it
- STOP always wins, from anybody
- Dead-man control: hold to go, release to stop
Sense → Think → Do
Still mostly DO, but now you can see the SENSE half on the phone while you drive.
How the session runs
- IR remote first: arrows drive, OK stops, numbers pick modes. No phone needed — this is the controller that works when the wifi does not.
- Connect a phone to the Workshop app. Watch the console: every button you press writes a line.
- Drive with the joystick. Notice the motor bars move as you steer.
- Two kids, one robot: one on the remote, one on the phone. Whoever acts first owns it; the other gets BUSY. Try to break it.
- Press 0 on the remote to release control, then let the other person take over.
Try this
- Drive a figure-8 around two chairs without touching either.
- Have a partner shout directions while you drive with your eyes closed. Notice how bad the delay makes you.
- Find the slowest speed the robot will still move at. Why does it stall below that?
When it goes wrong
| What you see | What it means |
|---|---|
| The phone will not connect | Bluetooth AND location must be on for Android Chrome. The page must be https or localhost. |
| Robot drives, then stops on its own after a moment | That is the dead-man safety: manual driving expires if the robot stops hearing from you. Hold the button, do not tap it. |
Notes for the grown-up
The arbitration demo is worth the time. Kids fighting over one robot is a management problem right up until it becomes the lesson.