I have started a little aquatic vehicle project that will be used to do depth mapping of the various ponds, lakes, and canals where I live in southern Florida. The mapping will allow the owners to determine their silt levels and silting rates.
My RSV is based on a similar RSV, only smaller, that appeared in the July/August 2010 issue of Robot Magazine and can be seen here: eTrac RSV
I chose to use fiberglass pontoons for a .60 size R/C plane and can be seen here:
The pontoons are manufactured by Great Planes and can be found at Tower Hobbies.
For propulsion I was originally going to build a couple of small outboard electric motors using Johnson-Mayfair 750GPM bait pump cartridges and 50mm Robbe three bladed propellers.
The housing for the bait pump cartridges was going to take a little bit of machining and the jaws in my Tag lathe still needed to be machined to allow me to chuck up plastic pipe couplers that are bigger than 1" in diameter.
Since I like Traxxas products, I found that the geared propulsion system for the discontinued Villain R/C racing boat might fill the bill as there are quite a few of the legacy Villain parts to be had on eBay for cheap:-).
So I downloaded the Villain exploded hull and drive train views and the parts list and proceeded to buy what I needed to put together two of the Villain geared propulsion drive trains.
At this time, while searching for Villain parts on Amazon, I found one last Villain built hull for sale and proceeded to order it so that I can build up a competition autonomous boat for competitions like the Sparkfun AVC only on the reservoir.
I began the installation of the Villain drive trains by cutting two sections out of the right pontoon just aft of the wire connecting bridge mounting points. I reinforced the sides and ribs of the pontoon, where I removed the fiberglass glass sections, with thin strips of poplar wood.
The toughest part of mounting the drive train was spotting the hole for the stuffing tube in the pontoon stern plate and getting clearance for the motor under one of the pontoon ribs. Pictures of the installation are below:
550 motor_reduction gears_and stuffing tube
Stuffing tube exit on stern plate
The propeller drive shaft is attached to a universal joint that is coupled to a short propeller shaft that is supported by an outdrive housing that is attached to a hinged trim support that allows the pitch of the propeller to be varied up and down vertically. I plan to epoxy the motor mount to the bottom of the hull once I have installed the rest of the propulsion hardware beyond the stern plate.
Right and Left Pontoons with Bridge
More build details and pictures to come.
Regards,
TCIII ArduBoat Developer
Replies
Great project. One question, what does the data look like? New to all this and was trying to figure out how to wireless connect a Hummingbird unit to a land station to get a good picture of the floor.
Phil
@Phil,
If the Humminbird Fish Finder has a serial output that provides depth/GPS position in an NMEA format (0183/2000) then it can be sent by a telemetry transmitter to a GCS for display.
My present setup records and transmits the GPS position sentence ($GPRMC) and the Depth/Temperature sentence ($SDDBT) to my GCS for display. I use Xbee 900MHz Pros running at 57,600 baud for the telemetry transmission.
I have an older Humminbird Fish Finder that dates back to the late '80s and uses four 40pin Microprocessors. It works very well, but does not have a built-in serial output and Humminbird Engineering would not tell me where I could possibly tap off a serial transmission of the depth. I would still need GPS position so the Adafruit GPS/Data Recorder Shield for an Arduino 328 along with the Garmin Intelliducer was the most cost effective way to go.
Regards,
TCIII AVD
I am tuning my skid steer boat right now and was wondering if you can post
a screen shot if your PIDs. Thanks
Eddie Weeks
Hi Eddie,
I presently use mostly default parameters and at the moment I have not had a chance to tune my RSV which has an APM2.6 that was in a rover and needs to have some of the basic parameters changed.
Please remember that the skid steering function in v2.46 does not function correctly and you need to use either v2.45 or v2.47 beta 1.
I might get a chance to tune the RSV this weekend if it does not rain here in Southern FL:-) This is the first time that I have used skid steering on a marine vehicle and I am taking it one step at a time.
I recommend that you start out with the following:
CRUISE_SPEED 2 - 3 m/s
CRUISE_THROTTLE ~30 - 40%
NAVL1_DAMPING at default and adjust as necessary
NAVL1_PERIOD start around 8 and adjust as necessary to minimize hunting.
Regards,
TCIII AVD
Hi All,
Yesterday I was able to integrate my GPS/Depth Finder NMEA 0183 sentence capture code with the Adafruit basic SD Data Logger code and proofed it out with just the GPS in operation in my garage. Since I have no way to properly load the Depth Finder transducer in the garage, I had to verify the code functionality without it.
On Monday I will go to the Association swimming pool and test the SD Data Logger with both the GPS and Depth Finder functioning. I can view the data capture and logging real time with my laptop over the telemetry link.
Regards,
TCIII AVD
Hi Tom, good work. My instruments are also temperamental about carriage return and line feed chr(10) AND chr(13). Some take one or the other and some takes both....odd, but it is what it is.
Good luck with the integrated testing - keep us posted.
Regards,
Antonie
Hi All,
During this week I have completed a telemetry link between the RSV and the GCS using Xbee 900MHz Pro transceivers.
Both transceivers are mounted in 3" x 2"x 1" black ABS utility boxes that I purchased at Radio Shack.
The GCS Xbee transceiver is mounted on a Gravitech Xbee to USB adapter board Link that is capable of supplying 250 ma of current for the 900MHz Xbee Pro. I may mount the case, as seen in the picture below, on a large plate to help stabilize it if I go to a higher gain rubber ducky antenna as they are typically larger than the present rubber ducky antenna.
I mounted the transceiver case on an extruded aluminum bracket to get it just slightly above the top of the Arduino/GPS/Data Logger water proof case as seen in the picture below.
Burkhard Rieck used the DrDepth application to display the GPS/Depth Finder NMEA 0183 sentences real time. Unfortunately DrDepth is no longer available and the only suitable replacement that I have found is UnderSee Explorer Link
The free version of UnderSee Explorer will allow you to display position and depth real time, but you cannot output any of the processed data and plots with the free version. A Professional version ($1295USD) is available that will allow export of the processed data and plots and many other advanced features.
If the free version meets my requirements, I will consider the purchase of the Professional version if I can parley the RSV into a profitable depth plotting business service.
Regards,
TCIII AVD
Tom, Do you have any ventilation at all in the container that covers your APM, gps, telemetry and receiver. I've always used this stuff on helicopters and never really had to be concerned with cooling. The clear plastic boxes could act as a little greenhouse's down here in the Florida sun.
Regards,
David R. Boulanger
@David,
For the short intervals that I have been operating the electronics on the RSV, I have used the covers unventilated or off, however I plan to drill 3/8" holes in the side of the cases where the lid hold down hinges mate with the case itself.
I will place the hole low on the backside of the case such that the lid hold down hinge, when engaged with the case, will block any direct spray of water into the case. I will also drill some 1/4" holes in the backside of the case near the top to vent the warm air that will collect in the top of the case.
The telemetry transceiver cases have 1/4" holes in either the top and bottom or sides and the top of the case to vent warm air out of the cases.
Regards,
TCIII AVD
Tom,
Just a quick thought I had. If you go to Home Depot and look in the home irrigation area you will find some 90 degree fittings for "Funny Pipe". They weigh very little and come in sizes from 1/2 to 3/4 inch diameter. My APM and related gear is mounted much like yours in a food storage container. Sooo.. I insert a couple of these barbs in the lower right side facing forward and angled down 45 degrees and a couple in the upper left side facing to the rear also angled down about 45 degrees. I think that would create a well ventilated compartment that is also spray/rain resistant. Savvy
Regards,
David R. Boulanger
-
2
-
3
-
4
-
5
-
6
of 13 Next