MANO

A 6-DOF arm on a mecanum base that takes instructions in plain language — Raspberry Pi 5, on-camera inference, and a spatial-reasoning model in the loop.

6Degrees of freedom
4WDMecanum, omnidirectional
~$400Total bill of materials
  • Raspberry Pi 5
  • IMX500 AI Camera
  • ESP32
  • PCA9685
  • Python
  • Gemini Robotics-ER

Why build it

I have spent years making software that never touches anything. I wanted a project where the feedback loop ends in a physical object either being picked up or being knocked over, because there is no arguing with that.

MANO — Mobile Autonomous Navigation Operator — is a mobile manipulator built out of hobby-grade parts on a budget under four hundred dollars.

The architecture

Split the real-time from the reasoning. An ESP32 drives the servos through a PCA9685 and owns everything with a deadline: PWM timing, the ultrasonic and time-of-flight sensors, the IMU loop. The Raspberry Pi 5 owns everything without one: vision, planning, talking to the model. They speak over serial with a small command protocol. A vision model stalling should never mean a servo holding a stalled position under load.

Inference on the camera. The IMX500 runs its network on the sensor and emits detections rather than frames. On a 4GB Pi that is the difference between a robot and a space heater.

Language in, poses out. Gemini Robotics-ER takes the scene and an instruction and returns spatial reasoning — what is where, what to grasp, in what order. The Pi turns that into joint angles. The model is a planner, not a controller; nothing in the closed loop waits on a network call.

Current state

Chassis drives. Arm moves through its full range under inverse kinematics. Grasping works on objects it has seen before, at known heights, on a flat surface — which is to say, in the easiest possible world. Everything after this is the hard part.

Where it’s going

I’m documenting the build publicly, and I’m interested in whether a hardware-plus-software subscription is a viable shape for a small team. That question is unresolved and I would rather say so than pretend I have a business model.

← All work