I’d like to share with you some progress, and very much hope that other people working on their BlueROV will do the same.
Bluerobotics, and Rusty in particular, have been kind enough to send me one of the first BlueROV. The parcel was perfectly packed and everything very well protected.
I’ve already assembled 90% of the kit (haven’t fixed the thrusters yet). Very easy thanks to the detailed step-by-step documentation. Still working (slowly…!) on the electronics and software. The BlueROV is a very elegant, solid and modular hardware kit. Much better than what I imagined during the Kickstarter campaign. You can tell that Bluerobotics team have put a lot of thoughts (and probably a lot of love :0) ) in its design.
I can’t speak much about the T100 (with BlueESC) yet… as I haven’t tested them in water. But it seems to be a solidly built product. And when applying a proper PWM signal, it turns, which is a good sign ;0) A couple of issues remain with driving the ESC through I2C; still working on it, with Rusty’s help. The latest documentation updates are important.
Shopping list (items that you’ll need to get while waiting for your kit, if you don’t have it already)
- "Marine epoxy" is recommended by BlueRobotics. In the US, it seems a fairly common product (Locite Marine Epoxy).
- Otherwise, Rusty told me that "standard" epoxy would do as well.
- In Hong Kong, where I live, I could not find anything named "Marine epoxy". So, I browsed many hardware shops, checked many epoxy brands and products until I found one that said to be suitable for boat repairs. This one was pretty thick, and not very easy to apply (impossible to use a syringe like in the documentation) - not sure if it will do. If somebody has some advice...
- Silicon sealant
- The flanges that were shipped with my BlueROV are different from the new ones available on BR's store. They require the application of silicon sealant between the flange's flat edge and the end-cap (while the new ones are based on an O-Ring).
- So if you receive the same flange as the one I have, get some sealant. I'd recommend white colour (not transparent), as it is easier to see that there are no air bubbles. If your flanges are with an o-ring, probably no need.
- Hex keys
- 2.5 and 3.0mm (can be purchased on BR's store)
Electronics - components to control / power the ROV
- Main board: Raspberry Pi 2B, in the ROV
- Camera: Raspberry Pi's camera module
- ESC: BlueESC (integrated in T100), driven by the Raspberry Pi's I2C bus
- Tether communication: Using Tenda P200 PowerLAN adapter (amazing idea to deliver high-speed Ethernet (AND power !) over 2 wires, described here)
- Depth sensor: MS5803 (OpenROV new IMU (30bar version) or CJMCU-MS5803-14BA (14 bar version) (Taobao / Sparkfun / eBay...) )
- 9dof sensor with fusion BNO055 (OpenROV new IMU or CJMCU-055 (Taobao / similar product from Adafruit) )
- Rasp.io Duino (Arduino on RPi) - very convenient. Useful to reprogram the BlueESC. May be useful in the future, to control potential submarine actuators (servos, motors). Regardless of BlueROV, if you have a RPi and would like to try Arduino, go ahead with this board.
- Environment sensors, inside the hull. I took this board, quite inexpensive (<USD10), embedding 3 sensors:
- Not decided yet:
- Internal battery charging system (BMS / PCM) (potentially charging during dive, for unlimited autonomy)
- Temperature sensor (batteries)
- OS: Raspbian Jessie (for native Gstreamer libraries that Whezzy do not have - not checked yet though)
- Main application: I'm going for Node.js (because asynchronous programming seems to fit our application so well). Not tempted by ROS for the moment :-)
- Video transmission:
- Already successfully tested low-latency transmission from RPi to RPi using Gstreamer over TCP (encapsulated h264 straight from the camera module ; no transcoding on the emitter side).
- Target: embed video in an HTML page. (WebRTC?)
- Control: probably Xbox gamepad over tcp or over http.
- Under study:
Hope to read from other BlueROV owners (or any ROV enthusiast of course)