Our original concept was the Marlin ROV a PVC based unit using common plumbing equipment modified to accommodate electronics this proved to be a good starting point as the parts were cheap and easy to manipulate and machine; the main limitations with design is the depth in which it can travel to we did rigorous testing a found that realistically we could get around 60Mtrs before the pressure housings would collapse or leak, hence we moved to ORCA MK4&5 this design allowed us to operate at 100Mtrs water depth before water ingress was noticed on our water detection system, Plans are available and combines ROV design and ORCA plans at our store a real bargain, all sales used to further our educational projects and are non profit.
The use of high pressure PVC tubing and hydraulic seals meant we could create a very cheap and cost effective unit that exceeded all our previous designs and proved to be a very useful tool, if you would like to build you own ROV plans are available from the store. This is a great tool for classroom teaching for technical studies such a craft and design or engineering and then can be used in biology for marine inspection duties.
Additional focus on auxiliary equipment include, Compass with pitch and roll, Temp sensors, Depth sensors, and feedback from the thrusters i.e. current in (amps). All scaling on the Hydra ROV can be preformed with the Arduino Mega or similar.