Use activity tracker as datalogging accelerometer 1

[ProEpro]

I was looking for a backlogging accelerometer and realized that is what the activity trackers like Fitbits do. Has anyone been able adapt one of those for engineering testing?
Can you get the raw acceleration data out instead of steps?
Which one do your recommend?


ProEpro

http://www.whitelightdesign.com

 

[TheTick]

I doubt Fitbit is going to open their API. However, you can probably access smart phone accelerometer API through their dev kits.

 

[IRstuff]

most accelerometers in those types of applications do not have high bandwidth

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[BUGGAR]

We tried using cell phones to measure acceleration of a large X-Ray machine that we moved on air bearings. It didn't work. They seemed to be a lack of sensitivity to our speeds. We just used the phones with no hacking.

 

[IRstuff]

Cell phone accels are also pretty noisy, in general.

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I can do absolutely anything. I'm an expert!
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[ProEpro]

I need something closer to the size and cost of the activity tracker then a phone. I just found the TI sensortag. It appears to do what I need but maybe too big. Are there other things like it that i should look at?

ProEpro

http://www.whitelightdesign.com

 

[Sparweb]

Long before the fitbit, joggers could buy step counters. Inside, nothing but a metal ball rolling around a cavity with metal plates on the walls. Every time the ball contacted two plates counted as a step. If you want to cheat, just shake the counter back and forth.

Toy ball for my kid had cheap accelerometers in it. Inside the ball was a cavity with a tiny circuit board and when the ball was bounced, LED's would blink. The accelerometers were just springs, one end soldered to the board. Around each spring was a metal tube, so if the ball was hit hard enough, the spring would touch the tube, making contact. Couldn't shake the ball hard enough by hand to make the spring contact, but dropping it on the floor worked every time. Until the dog chewed it apart, that is...


STF

 

[GregLocock]

Well if you gave us a bloody clue what specs you were trying to meet we might be able to help instead of playing guessing games.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[ProEpro]

minimum requirements
A datalogger with an accellerometer that will store and output acceleration data (I maybe able to use step counts).
1 hour of storage O.K. 1 week better.
size equivalent of fitness tracker roughly 6cm X 3cm x 1 cm. Smaller is better.
cost of less than $50 wholesale.

ProEpro

http://www.whitelightdesign.com

 

[IRstuff]

at what frequency?
at what resolution?
at what full scale value?
at what accuracy?

TTFN
I can do absolutely anything. I'm an expert!
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[Strong]

I think the required price of $50.00 wholesale answers all technical questions with the answer NO!

Walt

 

[IRstuff]

Not necessarily:

http://www.aliexpress.com/item/BJY6..._1&btsid=9512ab47-2a9a-40d4-b16a-745042e52497

add battery and use your cellphone or laptop as logger.

If not that, then:

http://www.ebay.com/itm/6DOF-MPU-60...005334?hash=item2ecca73356:g:BzkAAOSw9r1V-9c0

http://www.ebay.com/itm/ATmega2560-...163126?hash=item4afa5fd036:g:xYMAAOSwu1VW3JCj

TTFN
I can do absolutely anything. I'm an expert!
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[ProEpro]

Greg, this is why I am trying to adapt an activity tracker. All those types of requirements will be the same for my application. The only change I need is software access to the data.

Strong, there are activity trackers that retail for $50 which have the right hardware. So $50 wholesale is not unrealistic.

Thank you IRstuff. It looks like no one here has had any success adapting something. So I will need to get deeper into the hardware. These are very interesting options.

ProEpro

http://www.whitelightdesign.com

 

[IRstuff]

again,
at what frequency?
at what resolution?
at what full scale value?
at what accuracy?

TTFN
I can do absolutely anything. I'm an expert!
faq731-376 forum1529

 

[Strong]

Okay, so you can purchase an activity tracker for $50.00, and you believe that it provides the type of data needed for your project. Have you put any type/cost of activity tracker on your project and "looked at" or downloaded the data to see if such a device has promise? How much time and money will you budget to develop an interface and from programming?

Here is another approach to an activity tracker that might give you direct access to the data.

http://www.instructables.com/id/Make-your-own-activity-tracker/

Walt

 

[IRstuff]

$58 from

https://store.ti.com/eZ430-Chronos-915-Chronos-Wireless-development-tool-in-a-watch-P1736.aspx

The Chronos is a development kit, and includes access point to PC and software and is pretty much programmable

user guide:

http://www.ti.com/lit/ug/slau292g/slau292g.pdf

product page:

http://www.ti.com/tool/ez430-chronos

TTFN
I can do absolutely anything. I'm an expert!
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