Underwater Robotics-ROV&AUV

Differences between ROV and AUV

Underwater robotics is a type of robotics. The main difference with other robotics lower branches is that an underwater robot should be watertight. Because all the electronics may interact with the water. So if your robot leaks water, your robot will directly become inoperable. There are 2 types of underwater robotics: ROV and AUV. ROV and AUV are really different however they are thought to be totally the same. The main difference between them is the operation. ROV is manually operated by a driver and AUV is completely autonomously operated. You should have an ethernet cable for ROV to provide communication between PC and vehicle. In AUV, you do not have to have an ethernet cable, but you should have a good autonomous code. Also, you should have a better microprocessor in AUV for image processing or whatever you use for autonomous. You should have powerful lights too in AUV, otherwise, the camera won’t be able to detect the objects because of the lack of bright under the water.

Underwater Robotics Competitions

As I told before, ROV and AUV are really different so their competitions are different too. There are several competitions for ROV and AUV around the world. SeaPerch, MATE ROV, NURC, TEKNOFEST Unmanned Underwater Systems are some of the ROV competitions; RoboSub, SAUVC, European Robotics League are some examples of the AUV competitions. You can search for them on the net for further information and you can find which competition is best for you. I attended TEKNOFEST Unmanned Underwater Systems 2019 competition last year. We won the competition and it was such a great success for me and my team.

Watertight Products

In both ROV and AUV you should use watertight products. This is one of the most important parts of the underwater robotics. You should protect your electronic products and thrusters. We use 4" series watertight enclosure and 4" series dome end cap from BlueRobotics but you can use other watertight products too. Dome end cap is the place for your camera. It prevents your camera from water and also normally because of the light’s angle of refraction, with the camera you do not see the objects in their real place, with dome you can see the objects in their real place. You should use motors that appropriate to use underwater. Do not trust all the underwater motors that you see, certainly test it before you use it in your vehicle.

Electronics

There are several options in electronics. First of all, after you decide on your motor, you should find an appropriate ESC. Your ESC’s should be connected to an autopilot, Pixhawk Autopilot is one of the most popular autopilots. Pixhawk runs ArduSub control software which is used in underwater robotics. You can use Raspberry Pi 3B, Arduino, BeagleBone, etc. to provide communication between your computer and Pixhawk. Mostly, Raspberry Pi 3B is used but you can search and use the best one for your vehicle. Commands from your computers are delivered via an ethernet cable to Raspberry Pi. And also your camera vision is delivered via Raspberry Pi. If you use a USB camera, you can connect the camera to Raspberry Pi’s USB port, if you use the Raspberry Pi camera module, you can connect it to the Raspberry Pi’s camera port.

This was an overview of underwater robotics. If you have any questions you can reach me via email(aykan.orscelik@stu.bahcesehir.k12.tr) and you can follow for new writings about underwater robotics.