This Instructable was created in fulfillment of the project requirement of the Makecourse at the University of South Florida (www.makecourse.com)
***DISCLAIMER: This project has not been tested and is only a concept. Do not actually put this on a boat. Modified steering systems can result in death and should not be tampered with unless you know what your doing. Seriously, this is a concept only. DO NOT ATTEMPT TO USE THIS ON A BOAT OR ANY MOTOR VEHICLE***
Most marine steering system use a mechanical or hydraulic connection to operate. The Electromechanical marine steering system is an exploration into using electronic components to steer boats, with fly-by-wire controls, and universal compatibility for most outboards. By doing this, we remove the need of petroleum based fluids, expensive hydraulic hoses & steering cables, and create an easily modified boating experience.
I highly advise watching the video to become familiar with what the finished product is to look like.
Step 2: Items Required
The video above lists some of the parts used, as well as one of the previous designs of the project. This design was changed as it resulted in a lot of weight hanging in front of the engine. The initial design also integrated Bluetooth between the helm and outboard. This was scrapped unfortunately, due to time constraints, but can still be done by using two HC-05 modules.
As this is an ongoing project, the parts list is variable.
- Arduino Uno
- 2 - Multi Turn Potentiometers (Preferably 5-10 turn, 10k Ohms. You don't want your wheel to go Lock-to-Lock to Quickly.)
- 43 Amp Motor Driver (Or whatever you prefer to use)
- 24 volt, 350 watt Gear Motor (Again, Variable)
- 12 volt battery
- Assortment of wires & breadboards
- Access to 3d printer
- 12mm x 8mm Lead Screw
- 12mm x 8mm Lead Screw Flange (The lead screw & flange are usually sold together on eBay or Amazon.)
- 5/8" x 18" Threaded Rod (Homedepot, Lowes...)
- 5/8" Nuts & Washers
- Pillow Block Bearings - eBay (You'll need to edit the support brackets to hold your bearings. Just make sure that the bearings have a bore diameter of 12mm for your lead screw.)
Step 3: 3d Printing Your Parts
Begin by 3d printing your brackets and tiller assembly. I've included the IPT files for you to use. I used PETG for these, as the layer adhesion was much better than ABS. You'll want to make sure that these parts will mount to your lead screw and bearings, so modify as needed.
When modifying the parts, keep in mind your tolerances. It is very important that these parts are snug. Too much freedom between parts will result in twisting of the support brackets, eventually snapping your parts when torqued.
Step 4: Assemble Your Steering Mechanism
If you haven't noticed, there aren't many parts. I tried to keep it simple. The 5/8" Threaded rod will feed through the pivot tube of the outboard. The support brackets will mount to each end of the rod.
From here, you'll want to mount your bearings to the support brackets, and run your lead screw through both bearings. Thread your flange and pivot plate assembly on before running the lead screw through both bearings.
Mount your DC Motor to the end of the lead screw. You may need to modify your motor brackets to mount onto the support brackets. It ultimately depends on the motor that you purchased.
Step 5: Programming Arduino, Hooking Up Motor Drive & Helm
I used the IBT-2 Motor Driver when programming the Arduino. The sketch reflects their connections. The two pots will connect to A1 & A3. The sketch will compare the resistance between the two potentiometers. When the difference is great enough, the arduino will signal the Motor Driver to move the tiller in the needed direction.
Step 6: Print Helm
The helm is constructed of two parts, the wheel and base. You'll need to measure the shaft diameter of your potentiometer to ensure that it fits in the base & wheel. Once installed, run the wires from the potentiometer to the arduino.
Step 7: Test the Design!
Hopefully you made it this far. Again, the design is rough and far from being a usable product. But, it does allow for a lot of customization & improvement. Give it a shot and see what you can do! Good Luck!