Getting faster sensor (accel, gyro) reads/second with BLE

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I have some questions for a project I am working on that can hopefully be answered here…

The goal is to pass accelerometer and gyroscope data to a micro controller connected to a Bluetooth 4.0 chip and then relay that data off to a master device for analysis (let’s say an iPhone).

I was hoping for pure simplicity sake that I would be able to use a TI SensorTag in the initial prototyping and then move on to custom/smaller components later on. However the problem I am running into is that the accelerometer and gyroscope readings max out at about 20 readings per second (TI SeonsorTag to central device).

The sensor data is to be used then to map physical movements, so 20 readings a second is just simply not fast enough as I’m missing parts of the movements in between data reads. I’m thinking somewhere in the range of 250 - 500 readings a second would be more than adequate, and could probably get away with the lower end.

This being said I’m having to move further along in the prototyping phase to start to spec out and purchase hardware.

I had a couple parts in mind:

Triple Axis Accelerometer and Gyro Breakout - MPU-6050 (SEN-11038) (https://www.sparkfun.com/products/11028)

And was thinking of coupling it with the Blend Micro from RedBearLab (http://redbearlab.com/blendmicro)

I’m new to hardware development/design and was wondering if I would be able to reach the 250-500 reading per second I’m hoping to achieve with the above components. And if not what components you would suggest going with to reach these kinds of numbers.

Any help would much appreciated!

Thanks in advance.

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The datasheet specs the output data rate for both the accel and gyro to be above 500 readings/sec. So long as the other specs for dynamic range, sensitivity, BW, etc, etc meet your requirements … I don’t see a problem w/the 6050.

https://cdn.sparkfun.com/datasheets/Com … -6000A.pdf

I do wonder if BLE is the correct RF technology. It’s intended for short, infrequent messages. Your 6*16 bit (12 bytes < 20 data bytes allowed) minimum message is OK (I think) but I’m not sure about your packet rate and timing. 500 packets/sec might be too fast. You’ll need to dig into the BLE specs to be sure. But if you can’t be “Smart” then you certainly can use BT Classic.