Anyone who has attempted to construct an autonomous surface vessel understands the struggle to find a good hull. A few off-the-shelf options exist, but they are largely limited to boogie-boards, like the Maker Boat Basic, bait boats, and RC boats. Catamaran hulls provide excellent stability and mounting options for sensors for survey boats, like the HyDrone, but bare hulls often cost >$1000. A good hull truly is hard to find. After scouring the internet, we decided to construct a catamaran hull from a pair of kayak outriggers. We picked them up on Alibaba relatively cheap, but since they are intended for use with a kayak, it took a bit of work to make them into a catamaran. In the end, we designed and built a stainless steel frame that connects the two pontoons and provides mounting surfaces for the batteries, electronics, and propulsion.
Frame’s Anatomy
The frame consists of:
- The main frame that connects to the pontoons using four M6 bolts per pontoon
- A vertical tube to mount the acrylic tube that houses the electronics
- A Hollis Single Tank Adapter
- Stainless steel hose clamps
- M6 bolts with HDPE spacers to connect the single tank adapter (3) to the vertical tube (2)
- A HDPE pressure clamp that holds the acrylic tube to the horizontal members of the frame
Enclosure Attachment
When assembled, parts 2-6 connect the electronics enclosure firmly to the frame.
Pontoon Attachment
Fully Assembled
The fully assembled frame connects to both pontoons and has attachment points for the electronics enclosure, the thrusters, and the battery box. Wouldn’t it be nice if someone made an affordable catamaran frame for autonomous vehicle development? A good hull is hard to find indeed.