Virtual Mars Explorer: 6WD Rover With 6DOF Arm & Meta Quest 2 VR Control

This advanced Mars Rover project combines a heavy-duty 6WD off-road chassis with a 6DOF (Six Degrees of Freedom) robotic arm, all controlled via an ESP32 microcontroller. The highlight of this project is the immersive control system; we developed a web-based interface that allows users to pilot the rover and operate the arm using a Meta Quest 2 VR headset for a true "mission control" experience.

This project was designed and implemented by students from the Middle Technical University (MTU) in Iraq, Department of Space Engineering.

To build this rover, you will need the following components:

1. Mechanical Chassis: Black 6WD Car Chassis Damping Off-road.
2. Robotic Arm: Aluminium Robot 6DOF Arm Claw Mount Kit.
3. Microcontroller: ESP32 DevKit V1.
4. Motor Drivers (3x): L298N (to control 6 DC motors).
5. Power System: * LiPo Battery (3S 11.1V).
6. Buck Converter (Step-down module to 6V).
7. Sensors: * Ultrasonic Sensor HC-SR04 (Obstacle avoidance).
8. DHT11 (Temperature and Humidity monitoring).
9. Control System: Meta Quest 2 VR Headset.

We divided the assembly into two main mechanical parts:

1. 6WD Chassis: Assemble the six motors onto the damping frame. Ensure the suspension system moves freely to handle rough terrain.
2. 6DOF Arm: Assemble the aluminum brackets for the arm. Install the MG996R servos into the joints.
3. Final Mounting: Secure the robotic arm base to the front/center of the chassis. This ensures a good range of motion for the claw while maintaining the rover's center of gravity.

Watch the full mechanical assembly video here:

Black 6WD Car Chassis Damping Off-road

Aluminium Robot 6DOF Arm Claw Mount Kit

1. Component Mounting: Secure the ESP32, L298N drivers, and the Buck Converter inside a protective housing on top of the chassis.
2. Wiring: Connect the PWM pins from the ESP32 to the motor drivers and servos according to the diagram.
3. Common Ground: Double-check that all components share a single Ground (GND) line to prevent signal interference or erratic motor behavior.

MARS ROVER 6WD - ESP32 WIRING LIST

1. MOTOR DRIVER 1 (FRONT)
2. Right Motors (IN1): ESP32 GPIO 26
3. Right Motors (IN2): ESP32 GPIO 25
4. Left Motors (IN3): ESP32 GPIO 33
5. Left Motors (IN4): ESP32 GPIO 32
6. MOTOR DRIVER 2 (MIDDLE)
7. Right Motors (IN1): ESP32 GPIO 14
8. Right Motors (IN2): ESP32 GPIO 27
9. Left Motors (IN3): ESP32 GPIO 12
10. Left Motors (IN4): ESP32 GPIO 13
11. MOTOR DRIVER 3 (BACK)
12. Right Motors (IN1): ESP32 GPIO 19
13. Right Motors (IN2): ESP32 GPIO 18
14. Left Motors (IN3): ESP32 GPIO 5
15. Left Motors (IN4): ESP32 GPIO 17
16. ULTRASONIC SENSOR (HC-SR04)
17. VCC: ESP32 5V (or External 5V)
18. Trig: ESP32 GPIO 4
19. Echo: ESP32 GPIO 16
20. GND: ESP32 GND
21. TEMP/HUM SENSOR (DHT11)
22. VCC: ESP32 3.3V
23. Data: ESP32 GPIO 23
24. GND: ESP32 GND
25. ROBOT ARM CONTROLLER (PCA9685 I2C)
26. VCC: ESP32 5V
27. GND: ESP32 GND
28. SDA: ESP32 GPIO 21
29. SCL: ESP32 GPIO 22
30. V+ (Terminal): External 5V/6V High Current Battery (for Servos)

Managing power is critical for a rover with 6 DC motors and 6 servos.

1. Voltage Calibration: Use a multimeter to adjust the Buck Converter output to exactly 6V before connecting it to the ESP32 or servos.
2. Current Distribution: The 6V output powers the servos and the ESP32. The L298N motor drivers are connected directly to the 11.1V LiPo battery to provide maximum torque for the 6WD wheels.
3. Safety: Ensure a common ground (GND) between the battery, the buck converter, and the ESP32.

The ESP32 acts as a Web Server, hosting a control dashboard accessible via any browser, including the Meta Quest browser.

To experience the rover's mission in VR:

1. Connect: Put on your Meta Quest 2 and connect to the WiFi network "MTU_Mars_Rover_VR".
2. Launch: Open the Oculus Browser inside the headset and type the IP address: 192.168.4.1.
3. Command: The "Mission Control" interface will appear as a massive virtual screen. Use the Quest Touch Controllers to interact with the buttons.
4. Telemetry: Monitor temperature and distance data live as you explore your surroundings.

This project demonstrates the synergy between space engineering concepts, robotics, and VR technology. Special thanks to our colleagues at the Middle Technical University for their support. This rover is just the beginning of our journey into advanced space exploration robotics!