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DRV2605LEVM-MD: Help to find off the shelf product to transition form lab to prototype

Part Number: DRV2605LEVM-MD
Other Parts Discussed in Thread: DRV2605L, DRV2624, DRV2624EVM-MINI, ENERGIA,

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Just as I had problems identifying my needs for the DRV2605LEVM product, I am looking for help to find an off the sgelf product that I can use for prototyping. i used this product for proof of concept using ha[tic LRA motors to reduce symptoms of Parkinson's disease.  I am now looking tp find if there is an off the shelf product that can be  used in a prototype phase.  If possible, I am hoping to keep it low $$$.
I am using 10 LRA motors, one per finger.  They are all running at at 250Hz using RTP.  If all the motors are runnning the same parameters, do I need 10 haptic controllers (like the -MD board has 8), or can one controller handle multiple motors.  Depending on size, I would look for two units, one per hand (5 motors per hand). Alteratively, based on tech/cost, One unit controlling 10 motors is also acceptable.  I would need to adress the potential for alternate need of fewer motors (if a patient had an amputation, therefore <10 digits)
Because treatment can be as long as 4 hours, to facilitate mobility, a self contained battery operated unit is preferable
Thank you for your help.
Dr Branson

 

  • Hi Dr Branson,

    DRV2605L (&2605/2604/2624/2625) are considered dedicated haptic drivers because they will monitor the resonance frequency in real time and then drive the LRA motor at that frequency. this is ideal because it will maximize the vibration and minimize the power consumption. However if multiple LRA motors are connected to one DRV device this feature cannot work. We do not recommend multiple LRA motors on DRV26xx family. If multiple LRAs are used a cheaper higher current amplifier could be used. 

    My recommendation is to use 5x DRV26xx devices per hand, and a single host processor like an MSP430 Microcontroller.

    - DRV2624 is the same family of device as DRV2605L, the difference is DRV2624 cannot support 2V Vdd, and it does not have the integrated waveform library, however since you are using RTP mode the function, and prototyping complexity will be the same. https://www.ti.com/tool/DRV2624EVM-MINI DRV2624EVM-MINI is a small board that is intended for haptic prototyping. each board is 1cm x 1cm so the prototype can be small.

    - an MSP420 Launchpad like https://www.ti.com/tool/MSP-EXP430F5529LP can be used for the controller. these can be used for quick prototyping, and there is an IDE available which is very easy to learn called Energia https://energia.nu/ . this IDE removes much of the complexity, and is very well documented online. 

    - the DRV2624 has a feature called I2C broadcast mode, So all device can be written to at the same time. This can remove the I2C switches that are needed on DRV2605LEVM-MD.

    Regards,

    Arthur