This is the repository containing the code for the Imperial College London Rocketry CanSat, developped by the payload team.
To get started with the code, clone the repository to your local machine, then compile and upload the code using the file MasterCan.ino.
To compile the code succesfully, the following non-standard libraries must be installed:
The latter two can be installed through the library manager using the Arduino IDE.
Upon connecting the power, the CanSat should turn on automatically and begin setup. The green LED will turn on to indicate this, and will remain on as long as it is powered. Once setup has completed, the buzzer will do a short beep to indicate it has begun recording data.
The pressure sensor needs to be calibrated by setting the variable seaPressure to the sea level pressure of that day.
In the event that the CanSat encounters an error throughout its operation, it will save the code of the error to a variable, named softState.
It is a single byte where the error codes are each single bits. The individual errors can be found by getting the softState integer and converting it to binary. Alternatively, one can decompose it to its component powers of 2, as follows:
1 - ERROR: SD card initialisation failed
2 - ERROR: BNO055 initialisation failed
4 - ERROR: Failed to write to SD Card
8 - ERROR: Battery voltage low
For example, a softState of 12 would mean:
-
Battery Voltage is low
-
It is failing to write to SD card
Following from this, the softState can never be greater than 15.
Some errors mean that the CanSat will be unable to complete its mission. Such errors occur when a sensor or the SD card has failed to initialise. These will be referred to as "critical errors".
In the event of a critical error, the CanSat will return the softState via serial, the red LED will blink, and the buzzer will buzz intermitently until the Arduino is reset. During this state, no normal operations such as data collection are carried out.
In the event of a non-critical error, the red LED will turn on without blinking. The buzzer will remain silent. Otherwise the CanSat will continue with normal operation.
When the CanSat detects that it has landed, the buzzer will turn on and emit a continuous audio beacon. It will continue until the Arduino is reset.
To save storage space and make the CanSat more reliable, the data packet is as minimalistic as possible. It has the following structure:
packetCount:flightTime:pressure:temperature:altitude:velocity:batteryVoltage:softState:Xacceleration:Yacceleration:Zacceleration:Xorient:Yorient:Zorient:
All units are in SI.