Carrera vengeance faulty sensor? Add throttle?

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Evening all,

I've just purchased a poorly Vengeance E. The fault it came with was the motor didn't work and it had a very poor repair on the wires going into it. I've now re-done these and I'm happy to say when I press the walk button at the front the rear wheel now moves as expected.. However, when I pedal nothing happens.

I've located the DH Sensor with an LED which I would expect to light when it's triggered but this LED wasn't lighting at all. I've removed the sensor and had a look.. it fell apart just a little, well enough for me to think.. why not let's see whats inside. Measured the voltage on the neg and pos and it's reading 4.87 volts.. so I'm happy its getting power...

So, I'm thinking I'll need a new sensor. Is it only Halfords I can buy this from or is it quite a common one?

Also, I presume the sensor just generated a pulse signal.. either 3.3v or 5v I'm guessing to tell the controller that the pedals are moving. If I replicated this pulse via an arduino say.. would this work?


bb1.jpg bb2.jpg bb3.jpg
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
So.. just to see if I was correct. I've programmed an arduino up and loaded a simple 'blink sketch' like below


void loop() {
digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
delay(50); // wait for a second
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
delay(200); // wait for a second
}

I then wired it up to the pos / neg / signal (pin 13) of the cable for the bike and plugged it in.. Bingo, the back wheel started to spin! result. So, this has confirmed the sensor was faulty but also that if I can generate a pulse I won't have to pedal.. lol


Now to make or buy a throttle :)
 
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Woosh

Trade Member
May 19, 2012
20,448
16,915
Southend on Sea
wooshbikes.co.uk
I can give you a throttle and a pedal sensor head for free if you wire both to your Arduino.
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Yeah, happy to give it a go. Ideally the system would run on 5v.. so if the throttle is just a potentiometer then I see no reason why it wouldn't work. My current sensor is a 12 magnet type. I've found a compatible one on Amazon for £18 but would need to swap the plug over.

It would be nice to wire both to the Arduino... then if the throttle is being used it turns off the sensor but if the throttle is left at zero then it activates the sensor for pedal assist. However, the speed on the carrera is govenerned by the motor I think so you will still be limited to 15 mph. But at least you would have a throttle.... maybe :)
 

Woosh

Trade Member
May 19, 2012
20,448
16,915
Southend on Sea
wooshbikes.co.uk

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Thanks, email sent.

I'll do some more testing this morning to see if I can get a variable speed controller set up via a potentiometer and an Arduino.

Will posts the results later.

Steve
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Sadly can't find a potentiometer to test, although I have wrote the code ready. I'll have another look tonight maybe.
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
So I've managed to have a further play now I've found a potentiometer, it was in the last place I looked!

Anyway, been playing with the pulse range to see if I can get some sort of control. I can but I'm not sure if my motor is already damaged as it's vibrating quite a lot at high speed and getting warm. However, I have got some sort of control over it. With three speed levels via the power assistance button on the handlebars. I'll grab a video in a bit. I've been up and down the road a few times without peddling one bit.. not the safest as I need to rotate it to power it off.. but it's just for testing at the moment. I might design up and print a thumb control with a spring return tonight.

Steve
 
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Woosh

Trade Member
May 19, 2012
20,448
16,915
Southend on Sea
wooshbikes.co.uk
I thought you'd invent something for the old bike but did not expect you've done it so quickly. I am most impressed.
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
So, after realising the motor was actually faulty (was in the description when I bought the bike) I've had to source another motor. This is only a temp fix as I would like to fix my broken one if possible.

Anyway, quick video below. Yes, the back tyre is flat but I wanted to get the video done before the light failed as it's getting dark now. I might be able to push a little more speed out of it. Will do some more testing tomorrow.


More to come :)

oh, just remember this is a proof of concept. The final version will use a tiny arduino and a thumb throttle.. all the wiring and board will be nicely hidden.

Steve
 
Last edited:
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CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Sorry, updated the video link above... For some reason YouTube was still processing it. All done now.

Looking to add finishing of the Arduino code today and taking it out on a test run..
 
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Woosh

Trade Member
May 19, 2012
20,448
16,915
Southend on Sea
wooshbikes.co.uk
it seems to work very well.
the range of throttle control speed is well chosen too.
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Yep, the throttle range has about 500 different speeds, just need to see if I can improve the top end. Will really need to get it on the road to see if it achieves 15mph. The last motor struggled up hill, but I'm thinking that's because it was faulty. This new motor is off another non working vengeance I've bought... Let me know regarding the price for a replacement core :) would like to try and get my other back up and running really.

Thanks

Steve
 

CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
4CCA1D96-16EF-4D66-B798-37AF7835B5B0.jpeg Thanks :)

Just ordered a few of these tiny arduinos.. ideal for this job. They are really small and should fit inside the frame i hope. Be here by the weekend.

Steve
 

Woosh

Trade Member
May 19, 2012
20,448
16,915
Southend on Sea
wooshbikes.co.uk
throttle and pedal sensor are in the post.
You may need to cut and match the wires to the original wires and connectors.
Each has 3 wires: ground, 5V and signal. Usually ground is black, 5V is red and signal is any colour but black or red.
I was looking for a throttle with a long cable but all the modern thumb throttles have short tail with 3-pin yellow Julet connectors, so I have little choice.
 
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CdRsKuLL

Pedelecer
May 13, 2018
34
26
Bolton
lazylegs.co.uk
Great, thanks for this. Code will be finished and tested then I’ll send you a copy.

Been round the block a few times here and it’s working great. Getting decent speed :)

Steve
 

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