accelerometer

How to Count the Number of Steps Using the Accelerometer

i want to know how to calculate steps taken using the Accelerometer. Actually i calculate acceleration and use this code to count step

length = sqrt(x * x + y * y + z * z);
if(length>=2){
   stepcount+=1;
}

where length calculate acceleration using acceleration.x, acceleration.y,acceleration.z But my main problem at starting the application the stepcount gives correct step value but as time pass its value is not correct.Plz help me

Solution

  • Basically you're using sudden acceleration over a certain value as a sign that someone is ending or starting a step.

    First, you have to make sure you end up sampling the accelerometer frequently enough not to miss a step. Then you're going to have to make sure that you are guessing correctly about what your threshold should be.

    This is going to require a lot of trial and error.

    What I would recommend is graphing out what the length is over time and seeing if you can come up with a good threshold value that's usually correct.

    But, regardless, it's never really going to be accurate. I think the only way to really measure steps accurately is with a heel sensor in the shoe.