***The blog has been written a couple of years of back. Some of the information might not be relevant anymore due to obvious reasons. Please let me know if you find an error.***
IITB is surely is a great place for organizing technical competitions. The number of participants adding to the heat of the competition is just insane!
This semester, me and my friends, Shilpan, Aditya and Smit worked to participate in one of the competitions for Techfest’17.
Of the 51 participants, we were the only one who made a wireless Submarine which not only was wirelessly controlled but also had a camera on board which transmitted a live feed to the Fatshark. Our bot, Vandubbi as we call it, is a 45cm X 25cm X 25cm wireless Submarine specifically designed for search and rescue missions.
I’m making all the plans, CAD, STL files and a vivid documentation of the complete project open source along with the list of the technical challenges one faces in making such models from scratch.
List of technical challenges:
- Waterproofing: It is the most important factor, dude it’s a fucking submarine. Use Araldite wisely with a thick layer of duct tape or fibre tape. In case you’re drilling holes, drill many small holes rather than one big hole. Small holes are easier to waterproof.
- Mode for control systems: We preferred wireless controls over wired because this not only gave a really good number of DOF but also gives omits the resistance and heat losses offered by wires.
- Video streaming: We used Mobius Action CAM and Fatshark’s transmitter and receiver to get the live video to Fatshark. Using EasyCap we can even transfer the feed to Laptop/PC.
- Control: We have used RC Aeroplane’s remote control and configured it with Arduino to control motors and Electronic speed controller. BLDC have been used, yes they are waterproof!
- Structure: PVC pipes and some 3D Printed parts(Impeller including). Download the STL files from here.
In case you’re stuck with your project, e-mail me at email@example.com, I’ll try to revert back.
Vandubbi is a remotely operated underwater vehicle (UWV) (RC Submarine) which has the capabilities of being controlled wirelessly and is integrated with First person view (FPV). It is one of a kind because of its innovative and very efficient design. It is capable to manoeuvre for 20 minutes with a single charge of the batteries in still water with a payload capacity of up to 4kgs. Being wireless it is capable to do complex manoeuvres with relative ease than the conventional design. Being specifically developed for surveillance and underwater maintenance Vandubbi is a cheap replacement for existing expensive solutions.
A fully functional prototype of Vandubbi has just been completed and the team has started with the designing of the second version.
The testing video can be seen here. All the codes and 3D printable files of the Vandubbi V1 has been made open source under public domain.
Capabilities of the Submarine
- Vandubbi is capable of being controlled wirelessly and have a passive control system for roll stabilization.
- It has a theoretical range of more than a mile in line of sight, has been successfully tested for 300 meters.
- FPV and the onboard telemetry set gives the real-time acceleration, velocity and battery status along with a live feed from the camera which is transmitted to the Fatshark using 5.8Ghz frequency band.
- It has a payload capacity of up to 4kgs. An innovative bottle placement mechanism makes Vandubbi stable even if the load of the payload varies in space. The bottles attached at 4 different corners can change the amount of buoyant force on the UWV.
- A small focused LED is also placed at the front of the box which helps to get a better feed from the onboard camera in case of deep underwater excavation.
- The innovative failsafe mechanism ensures that in case of circuit or battery failure the bot automatically comes at the surface of the water.
Details about the funds required to build the second version are below:
|Item||Cost in INR|
|POWER DISTRIBUTION BOARD||200|
|TRANSMITTER AND RECEIVER||5000|
|BMP 180 SENSOR HIGH PRECISION||300|
|IMU SENSOR 9 DOF||1350|
|3D PRINTED PARTS||9000|
Total = ₹34850
I’ve used tons of open source resources to complete this project. This blog has documented my personal experience with Semi-Autonomous underwater vehicle.
To get your hand on the repository, email me at siddharth123sk[@]gmail.com