Actions
Forum Thread Details
  • State Suggested Answer
  • Replies 6 replies
  • Answers 1 answer
  • Subscribers 345 subscribers
  • Views 942 views
  • Users 0 members are here
Related

Primer for choosing the right accelerometer and gyroscope

Former Member

Greetings!

 

I am starting in this wonderful world called electronics, and as all the newbie, I have many questions, which I hope I will be able to answer trough this board.

 

I am starting a project that will involve various sensors, to measure the movements of the human body. So the choice of sensor fell on gyro and accelerometers. Mainly because I need to register the position in space, and translate it in a 3d environment. I will put them on something like a suit or other wearable items, so it should be easy to solder on the sensor.

 

The problem is: I have no idea where to start. I know how they works in general; I know that there are analog and digital version, and that they have different voltage to operate, and different sensitivity, but that's all that I know, and there are a ton of options.

 

I need basically a primer that would tell me, which "model" is used to a specific scope or use; so I can pick the ones that fits my needs. I am working with the human body, so I don't need anything fancy; the movements are mostly limited to hands or arms movements.

 

The choice among the ones with the specs that I consider right, are still a lot; and also the price is something that may vary wildly, so I hope that someone could shed some light about where to start.

 

I assume that there are various models, made by different companies, altho I fail to see the difference since the specs seems the same (same G, same voltage, same axis). Even the ones sold on Newark vary quite a lot.

 

Any suggestion is more than welcome; so I can avoid wasting money and time, on something that is not fitting my needs; and also avoid to waste money on something that is way beyond my scope (more is better, altho it is not my philosophy...I believe in the right tool for the right job).

 

Thanks in advance!

Parents
  • 0

    Hi,

    Cataloging all possible applications and determining the best sensor for each is a truly massive job and the whole table would need to be updated every week as new sensors are continuously being developed. It is unlikely anyone would attempt this as it would be a full time job and the resulting database would never be completely accurate. I doubt it is even possible to list all the potential applications. It sounds like you are already on track using the normal method of selecting devices, which is to list your requirements and compare specifications of the various devices to see which has the best fit. If you are not sure of how to specify your requirements, start with a detailed data sheet of n existing device and go through their list of specifications, but replace the spec values with values that fit your application. In other words make a new specification sheet using the cloned parameter categories. Then look for a device that fits these specs. If there are many devices that meet the requirements, choose lowest cost, or shortest delivery, or favorite supplier etc.

    In the case of accelerometers and angular rate sensors, the later models are usually better than earlier models. Typical specs to be concerned with are measurement range, bandwidth, size, power consumption, interface, cost, accuracy, supply voltage.

    Doug

  • 0 in reply to dougw

    Much appreciated, Douglas.

     

    It is very helpful the suggestion of the target fields on the data sheet, so I can pick the sensor that has the best price/features ratio. At the moment I am focusing on the Bosch BMA180, and the ADXL335 (preference for the second due to the lower price).

     

    There is also the ADXL345, but the cost is about 40% more than the 335, and the specs does not justify it in my case.

     

    It seems that almost any sensor support I2C, so I should be good to go; I will grab one of each and see which one fits better my needs; thanks!

  • 0 in reply to Former Member

    Before you spend your money look at parts from ST and Freescale, both make gyros and accelerometers. ST make boards with accelerometers and signal processing (and magnetometers) which might be helpful.

     

    MK

  • 0 in reply to Former Member


    As far as my concern ADXL335 doesn't Support I2C communication.
    It has analog output which is to be converted using ADC. So be careful about this.

    And ADXL345 has I2C support.

     

    Sumit Rai

Reply Children