ACCELEROMETER CONTEST. €50 reward

Development Boards Arduino
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HARDWARE: Arduino UNO. TinkerKit Shield. Tinkerkit Accelerometer.

AIM: I need to install an accelerometer into a CPR (cardio-pulmonary resuscitation) dummy to monitor the performance of the user during the time.

INTRODUCTION: The use of an accelerometer was already described in this way. Positioning the accelerometer inside the chest of the dummy and integrating the accelaration you will find the speed and integrating the speed you will find the lenght (or depth), that, in this case, is the movement of the chest toward the spinal cord (that is the data I need).

To have an idea you can take a look at this paper: http://www.ncbi.nlm.nih.gov/pubmed/22001002 (I can send you privately the copy, I can not make it public).

And to have a deep idea of what I want to do, you can have a look here: http://cache.freescale.com/files/sensor … pdf?fpsp=1

In the Freescale pdf you will find also an example of a program. What I want to do is exactly the same with my accelerometer but I have no skill, talent and time to do so. So I’m offering you €50 to do it for me.

WHAT I DID: To get an acceleration data from the sensor is easy, also for me. What is not easy is the integration beacause even if I’m ok with the math, the computation will get some errors at every calculation and these errors will accumulate giving me a rising integral even if the accelerometer is not moving. I tried all the logic stuff (semplification, casting, etc…), nothing worked, so I’m here to ask your help.

WHAT I NEED:

  1. A program that measures the acceleration on one axis (z), integrate this value twice to give me the depth of compression (movement).

  2. To integrate also one other (x) axis to get the “lateral movement” and so the efficacy of the compression.

  3. To plot these results (use processing, is quite easy, I did it but I need a better one).

  4. To store the resulting data in a txt-csv file (again, with processing it’s gonna be easy) to track the performance (usually 5 minutes) over the time.

  5. Eventual graphic and/or code improvements needed.

So the programs will be two: one for Arduino and one for Processing (or others if you think it’s better).

WHAT YOU WIN:

The first or best fitting code will be rewarded with €50 (PayPal ONLY). The final decision on the winner is only mine but your colloboration for the judgement is appreciated. If the winner decides that another member of the community contributed substantially to the final result, the second winner will get additional €20.

Thank you for your attention and time

Luca

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Methinks you might have had more response posting this as a interesting tech problem vs a pay-4-answer post. But who knows, perhaps a college student needing some beer $$s on a Friday night might give you a good answer. I’ll add 2 items to ponder :

  • While I can appreciate using an accel as a already “proven” means of measuring the compression, I have to wonder if a more direct measurement, given it’s going in a dummy, might be more effective and less $$s.

  • Given the impulsive nature of compressions I don’t think the double integration of accelerometer biases is a big deal. A slope test should be able to find the start of a compression and thus mitigate any built-up position error.

OK 1 more item … is the accel you’ve chosen up to the task ? I’ve not checked it’s specs nor have I tried to get an idea of what the req’s might be, but did you, prior to selecting the hardware ? Do you want the Arduino + shield + accel package to have to be mounted where they all will be moving with a compression or would an accel package, wired to a “remote” Arduino been a better choice ?

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I thought it would have been an easy task for a more skilled programmer than me…but maybe it is not.

The accelerometer shoud be up to the task upon my knowledge.

The acc will be alone on the dummy and wired to Arduino.

The slope test is a good idea that I’d try when I have time to put my hands on it again…

The use of an accelerometer gives you the possibility to measure instantly the vertical movement of the chest and also to quantify the eventual shifting of the compression direction monitoring the X axis.

What do you have in mind about another type of sensor? (Arduino, shield and accelerometer cost about $60 and i already have them)

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Given you already have the items you might as well use them. My thinking was if you’re using a dummy perhaps you could install a linear pot inside the dummy (obviously not something easily done with a live patient :twisted: ) and read the compression/distance directly. Perhaps have several pots in different locations if needed. I don’t know if this arrangement would allow you to “quantify the eventual shifting of the compression direction monitoring the X axis” though. Perhaps you could explain this part ?

Something like … https://www.sparkfun.com/products/9119