Submersible ROV for the Trondheim Maker Faire 2014

For the Maker Faire coming to Trondheim later this month, I’m currently building a simple submersible remotely operated vehicle. The concept is based on a plumbing tube used for the housing and submersible electric pumps as motors. A Raspberry Pi with Camera Module will deliver the live video feed via ethernet cable. The remote control is managed via a serial link to a Teensy 3.1 with sensors and motor controllers. The communication will be implemented using MAVLink, which enables the use of the QGroundControl station.

Outer Housing - Testing Outer Housing - with Ballast

After initially testing whether the tube could sustain the pressure at up to 12m water depth, pieces are now falling into place. The serial communication via MAVLink works and just needs a little performance tweaking. It can transmit the manual controls from a game-pad down to the ROV controller and the telemetry back up to the ground station. Telemetry data consists of air-pressure and temperature in the body (MPL115A2) as well as orientation data gathered from the IMU/AHRS (MPU-9150). The ground station visualises the temperature and pressure as line-graphs and uses the orientation information for an artificial horizon.

Inner Housing - View on Motor Controllers Inner Housing - View on PiCam and Raspberry Pi

The plumbing tube of the housing is sealed with two acrylic-glass windows. One 6mm one in front of the camera and three 4mm layers in the rear end. The three layers form tunnels for the cables going out to the motors and up to the ground control station. I hope with plenty of silicone this will be water tight.

Outer Housing - Frontview Outer Casing - Channels in the Backplate

If anyone has a good idea how to set up a basin/pool to demonstrate the ROV in, let me know.
Four weeks to go! 🙂

Maiden-Flight RaspberryPylot

RaspberryPylot made it!
With perfect weather and a great ground-team supplying me with food, the RaspberryPylot successfully completed its maiden-flight today. A laptop with gamepad, a wifi-connection using two simple USB dongles, an I2C servo controller and a Raspberry Pi and it’s ready to go:

 

Control via the gamepad was very comfortable and easy. Two analogue sticks for elevator, rudder, and ailerons. Two buttons to increase and decrease throttle and another two buttons to control the ailerons as flaps (flaperons). We didn’t test the master/slave mode today, but one can attach two gamepads and use one master button to switch between both with independent control profiles for each mode. In principle one could pass over the control of only one single axis at a time.

Many thanks to the CRRCSim team for creating such a fun way of training pre-flight.

Cheers
Tim