Making a radio-controlled submarine with Lego and other materials.To create a functional LEGO submarine, it all started with an airtight glass food storage container. The sub is built inside of a glass food container, chosen for its removable plastic lid with a watertight seal.
source/image(PrtSc): Brick Experiment Channel
This keeps all the mechanics dry, as well as the custom electronics built to allow a 27MHz RC controller to send signals to the Lego electronicsDepth control is done with an air-filled balloon and a Lego-compressor. The depth control I use here is called RCABS or Recirculated compressed air ballast system. Watch the video from Brick Experiment Channel:
Steering is done by turning the propeller direction with the help of linear magnetic coupling. Swimming pool and lake tests at the end.A ballast was added for neutral buoyancy, and once everything was completed, it was tested in a pool. The ballast system is simple.
When the balloon is filled by a Lego motor running an air pump, capable of 3.0 mL a second and capable of creating a maximum pressure of 2.0 bar. When the balloon is inflated, the buoyancy goes up and the sub rises. Run the motor the other way and the balloon is emptied by a clever clutch and valve arrangement, reducing buoyancy and causing the sub to sink.Brick Experiment Channel
- Displacement: 2.35 kg (5.2 lb)
- Test depth: 6 m (20 ft)
- Hull: glass jar (IKEA 365+ 1.7l), plastic lid
- Balloon: latex water balloon for kids
- Motors: 2x Lego PF L-motor (88003-1), 1x Lego PF Servo motor (88004-1)
- Compressor parts: Lego pneumetic pump small V2 (bb0875), Lego pneumatic switch (bb0874), Lego Gear 24 Tooth Clutch (60c01), Lego Hose Pneumatic 4mm (21825)
- Magnetic couplings: K&J Magnetics D34-N52 neodymium magnet, TapeCase 423-5 UHMW Tape
- Propeller: Lego Propeller 3 Blade with 24t Gear (2740c01)
- Radio control: 27 MHz controller dissembled from a toy submarine (Zantec Mini RC U Boot), L298 H-bridge to drive motors
- Power supply: 9V Lego battery box for the motors, 3.7V Li-Po for the radio
- Pressure sensors: Lego Manometer (64065), Jolly Logic Altimeter One