Electronics Update

There has been a lot of electronics work done since the first time I posted.

I2C Bus Build 

This needs further elaboration at a future date, but required lots of learning and experimentation. Was pretty satisfying when it all worked.

2015-11-09 19.55.18

TMP102, BMP180 initial concept working

2015-11-19 13.35.06

Final, with 4 I2C chained components

  • TMP102 0x72 (Master)
  • TMP102 0x73 (Slave)
  • BMP180 0x48 (Slave)
  • LSM6DS3 0x53 (Slave)

Power testing

Need to post final calculation of power draw, plus justified use of external power bank. JST to Barrel Jack vs Serial A-B input. Battery life can reliably last beyond 4 hours.

  • 2015-11-28 05.26.12







Inapplicability of “delay” and use of Arduino Boot-up clock

One of the custom solutions I needed to come up with was addressing time. When the telemetry package drew too little current, the battery (with a pre-programmed “smart” function) would assume that there was a leak rather than legitimate power usage. It would then turn off and there would be a “flicker” in the data.

Well, with lots of testing, I’ve learned that you learned that you lose about 60 seconds of data over four hours. This is betraying the use of the “delay” function, which is suitable for the use of single sensors (the time drift is around 1 ms per read), but not for a package like this.

Look ma, it’s Fritzing!
Screen Shot 2015-11-28 at 12.19.03 AM

Flight-Ready Code

I trimmed down and organized code for easy CSV export once we acquire all of our data. 16 columns, baby. Off the top of my head, I believe it’s…  time (ms), x acceleration, y acceleration, z acceleration, roll, pitch, yaw, Ozone, Ambient. Light, TMP102 external, TMP102 internal, IMU internal, Barometer Internal Temperature, Absolute Pressure, Pressure Relative to Sea Level, Altitude.

Screen Shot 2015-11-28 at 12.21.18 AM

With breadboarding done, here was the final soldered breadboard.6 7 8 9 10 11

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