This project is a part of PWSat2 Drop Tower tests.
- For free fall detection with ADXL345 clone the library from GitHub into your Arduino Lib folder.
- Upload the following into the board: code
- Drop the board from min 1-1.5 meters and see the messages in the serial monitor.
The shield can be bought from botland.com.pl
Responsible pins for controlling the relays are:
- Relay 1 (REL 1) D4
- Relay 2 (REL 2) D7
- Relay 3 (REL 3) D8
- Relay 4 (REL 4) D12
Important
Please not that using ethernet shield (for SD card capabilities) and Relay Shield together the relay 1 nad 4 needs to be switched off as the pins streering them are used by the ethernet shield itself.
For writing to SD the extnal Arduino library was used. The library is called SdFat and its much faster compared to the standard one available out of the box.
Executed tests with writing short strings into sd card:
| milis | x | y | z | state |
|---|---|---|---|---|
| 1058 | 7 | -35 | 6 | 0 |
| 1067 | 8 | -37 | 5 | 0 |
| 1076 | 8 | -35 | 6 | 0 |
| 1085 | 9 | -33 | 5 | 0 |
- x,y,z - readings from accelerometer
- state - additional data where FF indicates the point where the Free Fall was detected
- milis - time in miliseconds since the program started (used just for testing purposes)
Experiment data:
16.9 MB after 2.5 h of work
Example data can be found in the repo itslef under example-data.csv