Can I connect multiple vibrating mini motor disc to a haptic

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dofl1234
 
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Can I connect multiple vibrating mini motor disc to a haptic

Post by dofl1234 »

I am working a project for haptic feedback. I found below tutorial, Haptic Headband.

https://learn.adafruit.com/haptic-headband?view=all

Can I connect two 'Vibrating Mini Motor Disc' to a 'DRV2605L Haptic Motor Controller'? Will this setup lose vibration power by divining into two motor discs?

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dastels
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dastels »

I have no doubt that connecting more than one ERM or LRA will mess up the "smart-loop architecture" that's based on back-emf from the motor. I advise against it.

Dave

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Franklin97355
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by Franklin97355 »

It will probably work, it will depend on what you mean by "lose power". It will but you might not feel the difference.

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

Thanks for the quick answer. I got two different answers so what's right answer?

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dastels
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dastels »

The thing is, it's not just a motor driver that controls current going through the motor to make it spin (or oscillate in the case of a LRA). It uses back-emf generated by the motor to precisely control it. Having two motors connected will muddy that (since they are almost guaranteed to be out of sync ... they aren't just spinning shafts, they have an offset weight that effects the motions as well as creating the vibration) and degrade the result, likely significantly. As I said, it's a much more comples chip/system that just turning a motor on & off.

Dave

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

Thank Dastels for your answer. I just wand to control On/Off two motors together simply by setting pause in between On/Off. Will this work then?

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dastels
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dastels »

You don't need a haptic controller for that. You can use a DRV8833 breakout https://learn.adafruit.com/adafruit-drv ... kout-board that will let you control the two motors individually: turning them on/off or PWMing them.

Dave

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

Hey Dave,

I thought the haptic controller would be simplest solution to control the vibrating mini motor disc by following the tutorial. I am planning a wearable project so want to keep everything simple. For this reason, I am thinking of using GEMMA v2 as micro controller. I am not sure DRV8833 breakout work with GEMMA v2 because of lack of power/pins.


Thanks,
Dofl

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dastels
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dastels »

Fair point. But, since you are using the tiny pan motors (and not, e.g., hefty motors to drive a robot) and just need to turn them on/off you can probably get away with a simple transistor control circuit. See https://learn.adafruit.com/adafruit-ard ... -dc-motors.

Dave

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

I found same solution from below project originally but it looks a bit complex again using the haptic controller. I wanted to try to figure out with simpler option but you said it would not work.
https://learn.adafruit.com/buzzing-mind ... t?view=all

Any way to use two haptic controllers then? Otherwise I would go with the classic way.


Many thanks,
Dofl

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dastels
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dastels »

Since the haptic controller doesn't have an adjustable I2C address, you would need to use an I2C multiplexer https://www.adafruit.com/product/2717.

Dave

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

It looks the classical way would be the simplest option so far. I am not good at wiring so can I simply duplicate the wiring setup like the image I attached?

Dave, you saved my life.
Attachments
disc.jpg
disc.jpg (147 KiB) Viewed 238 times

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

Or can I just wire like this simply because I just control both discs at the same time.
Attachments
disc-2.jpg
disc-2.jpg (132.74 KiB) Viewed 238 times

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dastels
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dastels »

That looks right. pay attention to which pins on the transistor are what.

Dave

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dofl1234
 
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Re: Can I connect multiple vibrating mini motor disc to a ha

Post by dofl1234 »

It's so great to figure out simplest way to play two vibration discs by connecting to one control component. I'll order all components tomorrow morning and will follow your instruction.

Thanks a lot, Dave.

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