Project 9 Pet the XGO

Ⅰ. Teaching Aims

Read the status of the top touch pin A0 (Foxbit logo) to understand the principle of “capacitive touch”.
Avoid misjudgment through the process of “trigger → anti-shake → re-detection”.
Utilize if / else to respond to touch events in real time within the forever loop.
Be able to quickly replace the “actions after being touched” as needed, such as sitting down, turnning in circles, and performing randomly.

XGO + Foxbit + MicroBlocks IDE.
XGO battery power ≥ 60 %. The robot is placed in the center of a flat ground.
The copper foil on the top of its head is clean and free of oil stains. The wiring cable is firmly connected.
MicroBlocks status bar shows a green dot, XGO-lite extension is loaded and the development board model is Foxbit.
Run XGO reset pose to confirm that the zero position is OK.


Return value / Functions	`true / false` detects wheter it is touched
Fallible points	Wrong pin → always `false`

Return value / Functions	Perform different actions according to touching results
Fallible points	Forgot `else` → No touch, no movement

Return value / Functions	The action to be done after touching

Return value / Functions	The action to be done after touching

The following two scripts demonstrate common touch responses and can be directly copied and run.

Tap the logo on the top of the device gently, and the dog will immediately sit down and display happy.
After wait 5000, the emoji will automatically go out and enter the next round of detection.

Online code: Click here

Touch once → Turn left round once (40° × 9 times), and then XGO turn 0 to immediately stop.

Online code: Click here

What will occur if the anti-shake time is reduced from 50 ms to 5 ms?
Why must XGO turn 0 be written at the end of Test 2 while Test 1 does not require additional return?
How to put an action list such as “sit down, turn around, bow” into an array for random selection? Which MicroBlocks block is used to implement it?

Questions	Possible causes	Solutions
No response when touching	The copper foil is dirty / wires are loose	Clean the electrode; Reconnect the wire
Multiple actions when touching once	Insufficient anti-shake	`wait ≥ 50 ms`
Occasionally triggered by mistake	Electrostatic coupling /hand suspended too close	Add `wait 20` to the first line of the loop; Add a grounding wire to the copper foil
Always turning around	`XGO turn 0` is omitted or placed in the wrong position	Reset to zero immediately after the action is completed
The action gets stuck halfway	There is a conflict because other scripts are running simultaneously	Pause irrelevant scripts or use `launch` concurrently