Teensy 4.0 ADC for accelerometer readings

Hello everybody,

I am a Mechanical Engineering student and I am currently designing a DAQ system for a project for my school regarding vibration monitoring of a large structure.

I will be using 2 accelerometers for measuring the vibrations on the machine of interest and these, regarding the Teensy, will be the two inputs to the board. I want to install the system at the site where there will possibly be a USB cable exiting the electrical enclosure containing the Teensy and the rest of the signal conditioning unit, where an employee working at the site can plug the USB cable into their PC and get data for 5-10 minutes and then send the data back to me for analysis. I have very little experience using an Arduino Uno board for gathering data from one sensor to my PC during a school project using Putty to save the data into a txt file for further processing and analysis but my problem was that I could not figure out how to accurately set the sampling rate of the ADC at about 4kHz for the data acquisition. Since then I found out about many techniques which allow you to gather data and transmit it at the same time and I stumbled upon a post on the Arduino forums that said that the Teensy board is a much more capable tool for achieving my goal ( sampling 2 inputs at 5kHz ).

I wanted to ask if you think this is possible, and if possible some referral to specific techniques I should use. My biggest concern is the capability of the Teensy in regards to accurate sampling rate of 5kHz for both of the inputs I will be measuring and the data transmission to the PC. Also, if there is a better way to transmit the data to a PC I will surely appreciate any advice.
 
1. Teensy read speeds are very fast--not sure that will be a concern.
2. What accelerometer are you using? MPU6050 reads at only 1Khz, a ADXL345 is around 3.2Khz, I don't know of any 5K units
3. Are your accelerometers I2C / SPI based (bus speed is probably within limits), if so I don't think you need to be concerned about ADC speed.
4. Saving data may be a challenge, if you are saving 2 devices x say 3 floats x 5000 khz = 120K per second.
a) Using data to and onboard SD may be an issue
b) Saving data to the PC via serial (USB) at that rate should be OK.
 
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