Using accelerometer sensor to determine speed of person

Click For Summary

Discussion Overview

The discussion revolves around using an accelerometer (ADXL311) to determine the speed of a person running, focusing on the challenges of translating acceleration data into a usable speed formula. Participants explore the theoretical and practical aspects of data collection, processing, and calculation methods related to accelerometer readings.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant describes their setup with an accelerometer and expresses difficulty in formulating a speed calculation from acceleration data.
  • Another participant suggests that acceleration multiplied by the time increment provides the change in speed, which can then be added to the starting speed to find the new speed.
  • A question is raised about the placement of the accelerometer on the body, indicating that its location (e.g., feet or legs) significantly affects the method for calculating velocity.
  • A participant mentions achieving an implausible peak speed of 30 m/s and requests assistance in verifying their calculations and data collection methods.
  • One participant outlines their method of calculating velocity through the integration of discrete acceleration data using MATLAB, but acknowledges issues with data noise and seeks advice on proper data processing techniques.

Areas of Agreement / Disagreement

Participants express differing views on the methods for calculating speed from accelerometer data, with some suggesting basic principles while others highlight the complexities involved, particularly regarding data collection and processing. The discussion remains unresolved, with no consensus on the best approach.

Contextual Notes

Limitations include the lack of detailed information on data collection methods, potential noise in the data, and the assumptions made in the calculations. The discussion does not resolve the mathematical steps necessary for accurate speed determination.

cjn200
Messages
1
Reaction score
0
hello, I'm using an accelerometer (ADXL311) which outputs analog voltage in proportion to g's for X and Y axes. I'm trying to use this to manipulate sound when a person is 'running', basically as speed increases above a certain threshold, but having problems with my formulas for speed.

i've managed to graph these two actions with consistent visual results - it's visually clear when someone is running, etc., but haven't been able to correctly translate this into a usable formula. my known variables are gX, gY, time, and I'm assuming that i'll have to take periodic samples and calculate an average, but so far, I've managed nothing that makes sense.

can anyone help in a language for dummies? i can handle the electronics more or less, but had (embarrassingly enough :rolleyes:) to look the formula for speed.

thanks!
 
Physics news on Phys.org
I presume that they output an acceleration over their time increment. Acceleration times that time increment is the change in speed over that increment. Add the change in speed over that increment to the starting speed and you have the new speed.
 
Where on the body did you attach the accelerometer. If it is on the feet or legs you will need to do something very different find the velocity of the running person.
 
Hi everybody,
I desperately need help!
I am using tri axial accelerometer to calculate speed during sprint. I tried calculating speed and the peak speed from this data is 30m/s (which is not at all possible). I hv data at every .02 secs. I attached the acceleromater on sacrum.
please help..
 
You have not given nearly enough information for anyone to help you.

How did you calculate the velocity that you have?

How did you collect and process the data?
 
hi thanks a tonn for the reply.
I have calculated the speed like this.
Calculation of velocity from discrete acceleration data:

Integral of acceleration will give velocity value. Since data given for acceleration is discrete so we have calculated velocity value at x direction (Vx) through integrating under discrete acceleration data at x direction by using MATLAB programme. Similarly Vy and Vz was calculated. Total velocity value will be sqrt(Vx*Vx + Vy*Vy + Vz*Vz)
I didnot process data but directly used it (though i saw a lot of noise in data but not sure how to process it). could you please tell me about the correct way of collecting data and processing it and the correct procedure of calculating it.
IT will be a great help
 

Similar threads

Choosing Proper Filters for High-Speed Accelerometer Impact Sensing
  • · Replies 9 ·
Replies
9
Views
3K
Undergrad Is a car's top speed the same on a wet road?
  • · Replies 26 ·
Replies
26
Views
7K
Convert 1 phase to 3 phase by using an old washing machine
  • · Replies 19 ·
Replies
19
Views
4K
Undergrad Estimating Position with Noisy Acceleration Sensor
  • · Replies 8 ·
Replies
8
Views
7K
Undergrad Gamma - A Minkowski Spacetime Diagram Generator
  • · Replies 5 ·
Replies
5
Views
3K
I could really use some help picking my optional module [GameDev]
  • · Replies 2 ·
Replies
2
Views
3K
Angular kinematics: determining satellite orbital radius
  • · Replies 16 ·
Replies
16
Views
4K
Determining speed of an oscillating object
  • · Replies 5 ·
Replies
5
Views
6K
Second opinion needed at UAV Exercise
  • · Replies 3 ·
Replies
3
Views
1K
Undergrad Request for Input: 2D Minkowski Spacetime Diagram Generator
  • · Replies 6 ·
Replies
6
Views
3K