Mecanum Wheel Omnidirectional Robot Platform

Ordinary wheeled robots can only drive forward and turn — in tight aisles they must perform multi-point maneuvers like a car. Mecanum wheels solve this mechanically: rollers set at 45° around each wheel convert the four wheels' spin into any planar motion, including pure sideways strafing and spot rotation, with no steering mechanism at all. This project builds a complete mecanum platform: a fabricated aluminium chassis, four mecanum wheels on geared DC motors, independent H-bridge drivers, and an Arduino implementing the inverse-kinematics mixer that turns a desired velocity vector (vx, vy, yaw rate) into four wheel speeds. Drive comes from a joystick for proportional control and a Bluetooth phone app for convenience. The report derives the kinematics honestly and documents the measured strafing behavior — the part that makes examiners take the build seriously.

1. The desired motion — forward/back, left/right strafe and rotation — is read from the joystick or Bluetooth app as a velocity vector.
2. The Arduino applies the mecanum inverse-kinematics equations to compute each wheel's required speed and direction.
3. Four independent H-bridge channels drive the geared DC motors at those speeds via PWM.
4. The 45° rollers on the mecanum wheels resolve the four wheel motions into the commanded planar motion of the chassis.
5. The student runs the strafing calibration procedure, trimming per-motor PWM so strafe commands track straight.
6. Joystick mode demonstrates proportional omnidirectional drive; Bluetooth mode allows remote demonstration.

Tech stack:

• Arduino Uno/Nano (ATmega328P)
• 4 mecanum wheels (100 mm class)
• 4 geared DC motors (TT/BO class)
• Dual H-bridge motor drivers (L298N class)
• Analog joystick module
• HC-05 Bluetooth module
• Aluminium chassis (fabricated)
• Arduino IDE (C/C++ firmware)

• [True omnidirectional drive] Four mecanum wheels with 45° rollers give forward, strafe, diagonal and spot-rotation motion with zero steering hardware.
• [Inverse-kinematics mixer] Arduino firmware converts the commanded velocity vector (vx, vy, yaw rate) into four independent wheel speeds using the standard mecanum mixing equations.
• [Proportional joystick control] An analog joystick gives speed-proportional drive in any direction, demonstrating the platform's full motion envelope.
• [Bluetooth phone control] An HC-05 link allows drive from a phone app for demonstration convenience.
• [Independent motor drivers] Each geared DC motor has its own H-bridge channel, so wheel speeds are truly independent as the kinematics require.
• [Fabricated aluminium chassis] A rigid laser-cut/drilled aluminium frame keeps wheel geometry true — geometry errors show up immediately as drift.
• [Strafing calibration procedure] A documented procedure trims motor speeds so pure strafe commands produce straight sideways motion on the student's floor.

• Mecanum robot chassis with 4 wheels, motors and drivers
• Arduino firmware (kinematics mixer, joystick + Bluetooth modes)
• Inverse-kinematics derivation document
• Strafing calibration procedure
• Project report PDF, PPT presentation and viva Q&A document

• Mecanum rollers need flat, hard, clean floors — carpet, gravel or wet surfaces defeat the kinematics.
• Payload of approximately 2–3 kg is a design target for the specified motors; overloading stalls the rollers.
• Roller friction means mecanum platforms are less energy-efficient than differential drive; battery life reflects that.
• Pure strafe accuracy depends on the buyer-run calibration on their own floor surface.
• No autonomous navigation is included — this is a teleoperated platform (autonomy is future scope).