Hello everyone. I am planning to build a RC bodyboard boat with echosounder to make depth map of water bodies. Looking at the build made by rcmackay9 here I found that using submerged thrusters will cause debris to get stuck in the thrusters.
I was also curious if an airboat version can be made using the same sized body-board so as to eliminate chances of debris and aquatic plants getting stuck. If I plan to build an airboat, will it affect my efficiency and performance in any way when compared to submerged motor pod like T-200 thrusters?
I also noticed that with T-200 we get bi-directional motor which makes reversing of boat possible. Is it possible to make reversible airboat?
In short, should I go with submerged motor pods or with airboat?
If you want to do real surveys, you will not afford to see your boat stuck on the other side of the lake because entrapped by floating debris or submerged vegetation ingested by the submerged propellers
Consider also that if the power of submerged propellers allow them to “process” any kind of vegetation or debris, it will do the same also with the fingers of a curious kid that approaches the boat (also on the other side of the lake
Efficiency can be good with a proper design of the propulsion chain, and weight is not a major issue for this kind of drone
I think another alternative is to add some kind of stand-off between the frame and the thrusters. I think if the thrusters could be lowered 10 to 15cm it would greatly reduce the amount of debris that gets trapped in the motors.
We have built a few different boats…boogie board platform, modified from the great design of rmackay9 (Randy’s posts and info were of great help!):
We are in the process of upgrading this platform and are currently prototyping a using a kids kayak as the hull to offer more flotation and rocker in the hull. I did notice that we torpedoed the boogie board a couple times in large waves. We have also made a few airboats:
The airboats are very tricky to get tuned correctly, and they are highly power inefficient. We blast through a 30,000 mAh 12 cell in less than 30 min. The only reason we went with the airboat platform was due to the corrosive nature of the water that we were using it in, an abandoned mine pit…no moving parts underwater. They are very difficult to have the pixhawk control, they work best when going fast (5-10 m/s), and have no reverse. As a result I would not recommend an airboat as a surveying platform as you want to go slower (2 m/s), have the pixhawk accurately follow survey lines, and have a longer endurance in the water.
We have used airboats with custom fiberglass hull, they are pretty inefficient. We use EDFs for power, and proper rudder for steering. There is no issue with reverse though and pixhawk is perfectly capable to drive it.
We’ve got a wiki page with instructions on how to connect the HST-WSU 200. ArduPilot does not yet support reading in the temperature from NMEA devices but I will hopefully add support for this in the coming weeks and then hopefully include it in the Rover-4.1 beta release which should start within a couple of weeks.
We’ve added support for reading the temperature from a NMEA sonar and this will go out with Rover-4.2.0-beta2 within a couple of days. Txs again for the report.
Sorry I didn’t see your other comment earlier. To give some higher level information, you need to be using an ArduPilot compatible autopilot (there are many to choose from) and then you need to attach a “digitizer” (e.g. the DST-2) to the sonar to convert the analog signal to the NMEA protocol. Then you must connect this NMEA output cable from the digitizer to one of the autopilot’s telemetry ports as described on the wiki.
my dataflash has no DPTH - log_bitmask=65535 - how do we turn it on ? ardurover v4 pixhawk and ping1d which is using SONARRANGE nicely - just not logging…
Hi
How do I set the appropriate throttle? My differential control boat, which parameters can be set to make a gentle and gentle U-turn and sharp-angle turn, the action is too intense now
Can you post an onboard log of the vehicle doing a turn?
You’ve followed the tuning instructions on the wiki of course? There are two relevant pages, the most important is the turn rate control tuning. Next is the pivot control tuning.
@Marcel007
have you enabled one of the rangefinders within the parameters yet? Until you enable one of the rangefinders and refreshed parameters you will not see those until you do so. once enabled do a parameter refresh and you should now have a drop down menu with all those options.
By the way, we hide some parameters until the _TYPE or _ENABLE parameter is set to a non-zero value to reduce the parameter list for users. We have so many features in AP that we also have a massive number of parameters (well over 1000) so hiding some helps keep things manageable.
first of all I’ve bought echologger ect400 with serial output. The echo sounder has arrived and I am very enthusiastic about the first results on the pc.
However, I’m having trouble connecting to pixhawk (the orange cube). For the connection I am using a converter (I have already tried two different ones) rs232-ttl and despite all the parameters are set correctly as in the wiki (Echologger ECT400 echosounder — Copter documentation) the data did not arrive at the pixhawk. Also the converters microcontroller get very hot, and this seems very strange to me. The echo connected directly (rs232-usb) to the pc transmits data without problems. The converters get hot only when the ect400 is working. If for example I invert tx with rx (I’ve done it because I thought the connection was wrong), the max3232 get cold. I can’t understand what’s happening.
Thanks in advance for help/reply
