Ebike assist level control

Hi everyone, I'm trying to get a pedal assist selector that I can read out

I've just converted a touring bike to an electric one. I'm planning to go long distances and therefore I would like to make the switch from a thumb/twist throttle to something that can be used to select a certain assist level (that could correspond with a certain current level). I don't know the common term for it so if anyone could knows what it's actually called that would be great!

Preferably I'd like to use an off-the-shelf selector such as here:


Using one of these could save me the hassle of making my own selector.
I've hooked up the top one to a 15V lab bench power supply and checked the pins with a scope. There seems to be some kind of unusable signal but the leds respond normally to button inputs.

So my question for you is: have you got experience with using one of these selectors? Do you know if there's typically a certain communication protocol involved? Are there rugged stock selectors with a simple analog/I2C/UART/CAN output?

Thanks in advance!

Any KT (Kunteng) controller will give you what you wan. they have what the Chinese call "Torque simulation", which is current control. You can get them form most of the Chinese suppliers, Amazon, Aliexpress, Banggood, etc. The best LCD to go with them is the LCD3 because it gives access to all the settings. Avoid LCD1 and LCD5.

If you said how many amps you need, I could have pointed you at one. They have labels that look like this with KT designations:
https://ae01.alicdn.com/kf/HTB1iPYtas_vK1RkSmRyq6xwupXa3.jpg

Maybe I should've given a little background info. I'm using a Vesc 6 MKIV because of it's telemetry, open source software. I'm sticking to this controller for sure. Additionally, I'll be using a microcontroller to read out the cadence sensor, display telemetry, control the lights and so on. This will be on the bike regardless.

The only thing I'm not sure of is whether I should get an off-the-shelf selector and try to read out its outputs or make my own selector. Preferably I'd like to get the off-the-shelf but then I'd have to find out how it works. If anyone has info on how they typically communicate with the display or how the display controller reads them out that'd be of great help!

Etouring said:

Maybe I should've given a little background info. I'm using a Vesc 6 MKIV because of it's telemetry, open source software. I'm sticking to this controller for sure.

Click to expand...

Great! Sounds like you'll get to invent something.

I like to do that when it's mechanical or structural stuff. When it's electronic... I like to leave it to the guys with soft hands.

Well, I'm not opposed to inventing something. I'll find a solution for myself one way or another but would others be interested in an open source, perhaps programmable assist level button, maybe coupled with a display? Once the display comes in it'd get in Cycle Analyst territory but maybe just the assist buttons, being able to connect it to the CA could be interesting. What are your thoughts?

Etouring said:

others be interested in an open source, perhaps programmable assist level button, maybe coupled with a display?

Click to expand...

There are already several projects, doing exactly what you are describing, e.g. this:

https://github.com/prueferfrank/EBikeController/wiki

https://github.com/haditim/ESP32-VESC-eBike

If you are looking just for a button pad you could use something like this:


If you want a display combined with buttons, you should use a Kunteng LCD-Display.



The used UART protocol is well known and ready to use libraries are available.
https://github.com/stancecoke/BionX_Minimal_Translator/blob/master/Src/display_kunteng.c

regards
stancecoke

That button pad looks exactly like what I'm looking for: low cost and probably really easy to read out. I'll probably order the one you sent and make an update/thread comparing a few different ones. The links you sent are helpful and while I'm not looking for a button pad combined with a display, I'll keep them in the back of my mind for further development.

Still, if people are interested in a small standalone button pad (for a cleaner look perhaps) that could be programmed to do UART/CAN/analog out I'd be happy to investigate what's possible!

Bought a digital switch from Grin to control my assist level.

Aux Input

Etouring said:

low cost and probably really easy to read out

Click to expand...

casainho uses this button pad for his ANT+ LEV project . There are just switches in the pad without any additional electronics:



regards
stancecoke

A little update:

Thanks all that replied, @stancecoke for the further info and @ZeroEm for pointing me to the Grin Technology one. I knew their shop but never saw the Aux input section! After seeing the lead times for Europe and probably some shipping, I decided to buy the one from Giant since its ' cheap', has 6 buttons and is small. I opened it up, sacrificing it in the process and found out it has a circuit similar as the one from casainho, with buttons shorting to GND. Perfect! The only downside is that the cable is short and the connector doesn't seem familar. It looks similar to a Higo one but seems different than the standard Julet/Higos. It's an 8-pin connector.



Does anyone know where I could find the complementary connector (apart from the display where it can be attached to)? That will allow me more freedom in the placement of the button pad.