When I was designing a backpack system, I thought the best method to measure force was via a tube and an air pressure sensor.
The end of the tube could have a bulb on it which could be squeezed with a hand or in your mouth.
Hall effect sensors used in remotes like the maytech probably use an I2C chip, which means you could probably swap it out for an air pressure sensor and use the same throttle calibration process.
Using air makes the connection methods cheap and easily replaceable incase it is broken, and there would be no electronics in your mouth.
Sounds interesting!
I recall seeing something similar before (possibly your suggestion), but I didn’t fully grasp it at the time and dismissed it, thinking it was related to blowing air.
Also the advantage of a balloon is that it provides tactile feedback of contraction.
Using electronics somewhere near the head is inevitable anyway, since it needs to include a battery state indicator and power/lock button. But it could be split somewhere on the backpack strap in front…that is an option
Regarding engaging maytech - are you specifically referring to using their receiver rather than the remote control unit?
Could you clarify which calibration process you’re talking about? Is it the one done using the Maytech remote?
I’m curious about why we need to use proprietary remote hardware at all - wouldn’t it be simpler to perform manual calibration and use ESP32? Is it that hard to calibrate throttle?
Also, I’d be interested to hear about your backpack system…
To update on my future plans - It will be a wireless remote.
Cons of wired setup:
Worry about wateproofing cable at the box and at the remote
Worry about passing the cable.
Passing the supply in the cable.
The feature of wireless disconnecting in the water is important for security.
Less flexible overall.
Wireless remote has to have battery and has to be charged wirelessly. For the later there are readily available minituare modules. If there is no display, gps etc. and the rf is done smart, battery can be very small. So eventually this remote will be able to be used in the mouth.
If you use a VESC based controller, you can use ADC throttle directly. That’s a simple 3 wires cable. GND, 3.3V, and Signal. Thumb throttle, or mini joystick can be in a soft bag that is sealed around the cable.
Sure, your throttle won’t tell you how much battery’s left or how long you’ve been out, … but simple is good! And you could have that info on your phone anyway.
If you want to be fancy (and/or overkill), you can use M12 connectors and cable assemblies, available with different ratings including IP68.
While building a simple tow boogie and a backpack I often felt that a simple throttle with a kill switch would be a good alternative to current options. In practice, I don’t know whether it would be preferable, but it seems like it could be useful, and cheap.
Example boat kill switch
Something else I think is an issue with tow boogie is having to hold the remote in the same hand as the tow handle. For some this is less of an issue if they have preference, but both the handle and the throttle are more comfortable in my right hand. You end up wit the handle in a few fingers and suboptimal grip.
I think once you get better and ride waves and or pump it might be better to keep the remote in your hand so you can let the towboggie follow you. Needs a way to steer it, 2 motors and new bremote. This scenario is a point against throttle in the handle bar.
Working on the wired solution too for a backpack unit, using vesc to keep it simple and be able to plug in with a 3 wire ebike thumb throttle.
These options have have voltage meters, may work for many battery set ups, 12s in my case. Wondering what’s the best know practice of waterproofing things like this.
Other way is to use a cable operated throttle controller similar to what surron uses and figure out how to waterproof the cable with a fitting on the box.
My idea is to have hands free at any given moment. Just drop the throttle and have it reel or bungee back to my side/hip. Leaving me free to flap my wings, duck dive, swim to and grab the board
