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Case18：Color-controlled TPBot

Purpose​

  • The rainbow LED changes in accordance with the color of the cards and it executes the defined functions accordingly(move forward;change the color of the headlights at random; obstacles avoidance; line-following)

Material​

Hardware connection​

Connect rainbow led to port 1 and color sensor to IIC port on TPBot.

Software​

MicroSoftmakecode

Programming​

Click "Advanced" to see more choices in the MakeCode drawer.

  • We need to add a package for programming. Click "Extensions" in the bottom of the drawer and search with "tpbot" in the dialogue box to download it.

  • We need to add a package for programming. Click "Extensions" in the bottom of the drawer and search with "PlanetX" in the dialogue box to download it.

Sample​

  • In on start brick, drag the show icon brick into it and initialize the led strip and has it connected to J1 port.

  • In forever brick, set the rainbow led in white if the color sensor detects white, and set TPBot move forward at the speed of 30%.

  • Set the rainbow led in red if the color sensor detects red, set TPBot stop moving and the RGB value of the headlight a random number among 0~225.

  • Set the rainbow led in yellow if the color sensor detects yellow, and judge if the returned value from the sonar:bit is between 3~20. If yes, set TPBot turn left for 1s at the speed of 30% or move forward at the speed of 30%.

  • Set the rainbow led in green if the color sensor detects green, and judge the status of the two-way line-tracking sensor. If black is detected on the left, set the speed of the left wheel as 0 and right as 40; if it is detected on the right, set the speed of the left wheel as 40 and right as 0; if it is detected on both sides, it means the TPBot does not deviate from the black line, and set it move foreward at the speed of 25%.

  • Set the rainbow led in blue if the color sensor detectsblue, set the TPBot stop moving.

Code：

Conclusion​

  • Place the cards in different color in the front of the gesture sensor to activate different functions:
  • White card: Rainbow LED lights on in white and TPBot moves forward.
  • Red card: Rainbow LED lights on in red and TPBot stops moving with the headlights changing the colors at random.
  • Yellow card: Rainbow LED lights on in yellow and TPBot goes into the obstacle-avoidance mode.
  • Green card: Rainbow LED lights on in green and TPBot goes into the line-tracking mode.
  • Blue card: Rainbow LED lights on in blue and TPBot stops moving.

Exploration​

FAQ​

Q: While operating this case, why the car might not work properly? A: It might be the low power of the batteries, please try adding the value of TPBot's speed and test again.

Relevant File​