18 June 15
Yesterday we completed the code for the I2C driven magnetometer. Counting all sensors we are now able to measure the following parameters:
3 Axes of Acceleration (g's)
3 Axes of Magnetic Field Strength (Gauss)
Internal Temperature (Kelvin)
External Temperature (Kelvin)
Barometric Pressure (Kilo Pascals)
GPS Position Data.
Only sensor left to get up and running is the sound sensor
We ended up having to solder together a second ribbon cable, only 2 connectors of which are used to link the gps serial lines. 2 more will be used for the sound sensor. Last evening I took the gps home and allowed it to run for quite some time under the sky. I was reading a book and periodically checked on it, but the first time I noticed it had gps lock was after ~45 minutes. After that the lock was intermittent since where I had set it up was under some large trees. Once it was moved into a clear area it had no problem maintaining lock.
A bug was discovered in the code and fixed. The gprmc variable that stored the gps data was created within our data collection loop. What this means is every second when we sampled our data again, the variable was re-created in a null state. The problem with this is that if the serial fails one transmission (Happened on our first long test after 1247 data points, 20 minutes 47 seconds) when the program tries to write to the file it throws the error gprmc has no attribute named datetime or longitude etc. This has been remedied by defining the variable before the loop so if the serial fails it can only do so on the first data point and we can check that on the ground. If in flight it skips a transmission then the file will still write, it will just have the gps data from one second ago so no major loss.
3 Axes of Acceleration (g's)
3 Axes of Magnetic Field Strength (Gauss)
Internal Temperature (Kelvin)
External Temperature (Kelvin)
Barometric Pressure (Kilo Pascals)
GPS Position Data.
Only sensor left to get up and running is the sound sensor
We ended up having to solder together a second ribbon cable, only 2 connectors of which are used to link the gps serial lines. 2 more will be used for the sound sensor. Last evening I took the gps home and allowed it to run for quite some time under the sky. I was reading a book and periodically checked on it, but the first time I noticed it had gps lock was after ~45 minutes. After that the lock was intermittent since where I had set it up was under some large trees. Once it was moved into a clear area it had no problem maintaining lock.
A bug was discovered in the code and fixed. The gprmc variable that stored the gps data was created within our data collection loop. What this means is every second when we sampled our data again, the variable was re-created in a null state. The problem with this is that if the serial fails one transmission (Happened on our first long test after 1247 data points, 20 minutes 47 seconds) when the program tries to write to the file it throws the error gprmc has no attribute named datetime or longitude etc. This has been remedied by defining the variable before the loop so if the serial fails it can only do so on the first data point and we can check that on the ground. If in flight it skips a transmission then the file will still write, it will just have the gps data from one second ago so no major loss.
Comments
Post a Comment