Building a Lego powered Submarine 3. 0 balloon and compressor

Depth control is done with an airfilled balloon and a Legocompressor. Steering is done by turning the propeller direction with the help of linear magnetic coupling. Otherwise it s more of the same as before. Swimming pool and lake tests at the end. Enjoy Specs: 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 Lmotor (880031), 1x Lego PF Servo motor (880041) 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 D34N52 neodymium magnet, TapeCase 4235 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 Hbridge to drive motors Power supply: 9V Lego battery box for the motors, 3. 7V LiPo for the radio Pressure sensors: Lego Manometer (64065), Jolly Logic