Wichit Sirichote, firstname.lastname@example.org
Simple Micromouse KIT, UKMARSBOT platform, controlled with MEGA328 NANO board.
This simple design micromouse is based on the UKMARSBOT platform. The controller is MEGA328 nano board. Motor driver board is TB6612FNG. This hardware version is modified from the original design by Peter Harrison, UKMARS.ORG The wall sensor has 3 directions: RIGHT, FRONT and LEFT. Wall detected indicators are added using three colors LED. The master reset button is also added. The robot is powered with two cells, series connected, 14500 Li-ion battery (+7.4V). The N20 motor with encoder is mounted on the PCB using the available holder directly. The software examples and test code are compatible with ukmarsbot.
Micromouse T01 features:
- Main body: 86x99mm
- Wheel diameter: 34mm
- Ground clearance: 10mm
- Height (with battery): 50mm
- Weight: 90g (no battery), 150g (with Li-ion battery)
- Motor mounting nut: M2
Hardware schematic (click to enlarge)
Hardware: The wall sensors produce analog signal proportional to the amount of reflected IR wave. Three phototransistors for RIGHT, FRONT and LEFT directions are connected to the analog input A0,A1 A2. The IR emitter is switched ON by Q2 transistor. The wall detected indicators are. D10 for left wall, D9 for right wall and D2 for front wall. D10 is shared with bootloader LED on NANO board. During code downloading, it will blip at power on reset, or manually reset by SW3 pressed. D2 LED is shared with system tick indicator.
Power output to the motor is PWM signal driven by TB6612, dual channels H-bridge DC motor driver. The control signals for left and right motors are PWM, and direction. The encoder wheel is magnetic disc attached to the motor shaft. The HALL sensors detects motor revoluation, produing DC pulse to the interrupt pins of the 328 chip.
The function selector produces 16 voltage levels. This voltage signal is tied to analog input A6 pin. User can set 16 functions with four bit binary number from 0000 to 1111 for function 0 to 15 directly.
Nice design, PCB layout.
REAR VIEW, Power switch, Start button, and Function select 0-F (0-15)
With Li-ion 14500 battery, +7.4V, placed on the battery frame.
Robot can connect terminal for program testing. The speed sets to 115200. Press START button the robot will send data stream for sensor readings, robot position, robot angle.
Terminal connected, 115200 speed, FUNC sets 0001, shows Left, Front ad Right sensor readings. (Left and Front detected!
Sensor test function 1 (0001): Left and Front walls are detected.
Sensor test function 1: Front and Right walls are detected.
Sensor test function 1: Left, Front and Right walls are detected.
DIY maze 4x4 (180mm cell size). Yellow LED shows Right wall detected.
The micromouse T01 is available on eBay in kit form.
Miromouse T01 Kit form
U1 328NANO, MEGA328 NANO board, 16MHz
U2,U4,U6 5mm phototransistor
U3 TB6612FNG, 2-channel motor driver
U5 74HC86, quad exclusive-OR gate
D1 1N4148, Silicon signal diode
D3 1N4733A, +5V zener diode
D8 TVS15V, Transient Voltage Suppressor diode
D2,D9,D10, 3mm LED
D5,D6,D7, 5mm IR LED
Q2 BC337, NPN general purpose transistor
Resistors (all resistors are 1/8W +/-5%)
C1 220uF, 16V Electrolytic capacitor
C2,C3,C5,C6,C7 100nF, multilayer capacitor
C4 470uF 16V Electrolytic capacitor
MG1 N20 gear motor with encoder
MG2 N20 gear motor with encoder
SW2 DIP switch 4-position
SW3 MASTER RESET button
SW4 Slide switch power ON/OFF
JP1 4 pins header for HC-06 Bluetooth MODEM (optional)
J1,J2 CON6, female 6-pin header
J3 CON2, Battery socket
K1,K2 Fixed Wheel
LS1 BATTERY FRAME
PCB double layer printed circuit board
M2 motor holding nut x2
M2 Nylon tube 15mm x4
Micromouse T01 Kit is available on eBay.
Bitcoin or PayPal are also accepted.
Assembly Manual, rev1.0 December 2022
Schematic , BOM , Test code for T01 Bot , Quick Start
Software example UKMARSBOT at github
More technical information, please contact Wichit Sirichote, email@example.com
Last updated November 3, 2022