MuTech RoboticsLearning Hub
Kids OK with adultESP32Level 2/3

Tea-Serving Robot

Pick a desk on your phone. The robot follows a black tape line and stops at that desk with your tea.

Tea-Serving Robot
Kids OK, with an adult

DIY project. Children must build this only with an adult (16+ years) beside them at all times. Not suitable for children under 8 years.

An adult must handle and charge the lithium (18650) batteries.

Strictly follow the description given with this video.

Video

The video link will be added here soon.

How it works

  1. Three IR sensors under the robot see the black tape line (left, centre, right).
  2. The ESP32 steers: if the line drifts left, it slows the left motor, and the same for the right.
  3. White stop marks across the line are counted. At the chosen desk number, the robot stops.
  4. The L298N driver gives the motors the battery power that the ESP32 pins cannot give.

Parts you need

  • ESP32 dev board× 1Buy
  • 3-channel IR line sensor (TCRT5000)× 1Buy
  • L298N motor driver× 1Buy
  • 2× N20 6V gear motors + wheels× 2Buy
  • Ball caster× 1Buy
  • 2× 18650 battery pack (7.4V) + ON/OFF switch× 2Buy
Kit for this projectPrice on request
Get the kit

Wiring

Wiring diagram
PowerGroundSignal
#FromConnect to
1 PowerIR sensor VCCESP32 3V3
2 GroundIR sensor GNDESP32 GND
3 SignalIR sensor LESP32 D5
4 SignalIR sensor CESP32 D18
5 SignalIR sensor RESP32 D19
6 SignalL298N ENAESP32 D14
7 SignalL298N IN1ESP32 D27
8 SignalL298N IN2ESP32 D26
9 SignalL298N IN3ESP32 D25
10 SignalL298N IN4ESP32 D33
11 SignalL298N ENBESP32 D32
12 SignalL298N 5V outESP32 VIN
13 GroundL298N GNDESP32 GND
14 SignalLeft motorL298N OUT1 / OUT2
15 SignalRight motorL298N OUT3 / OUT4
16 PowerBattery +Switch → L298N 12V
17 GroundBattery −L298N GND

3D print files

  • robot_chassis.stlPETG · 0.2 mm · no supportsLink at launch
  • cup_tray.stlPETG · 0.2 mm · no supportsLink at launch

Code

The tested Arduino / ESP32 code for this project will be posted here, ready to copy.