This is our second prototype for the flight computer that was used in our first two test flights where we gathered data and tested sensors. Here you can see the pressure sensor (left-most component), IMU (the component near the center), and SD card reader (right most component).
The inertial measurement unit (IMU) is responsible for measuring the rotation and acceleration of the rocket. We need to ensure that it records information accurately in real-time. To test it we spun the test stand on a lathe at a known RPM (verified by both the lathe's RPM counter and by using a phone flashlight flashing at a set frequency). So far, this has been the only sensor we've tested.
The above lathe test-bench gave us meaningful test data, in this example we spun the lathe at 100 RPM. The data's average is 100 RPM. This is great, but we need accurate live data. So we need to implement filtering to smooth over some of the peaks and valleys.
Raw data before filtering
To smooth out the noise in our sensor data, we implemented a digital filter that reduces peak and valley spikes while preserving the overall trend of the data. This filtering technique allows us to get more reliable real-time measurements for our control system feedback.
Collect initial flight telemetry from the rocket.
Incorrect firmware was uploaded to the flight computer prior to launch.
The rocket launched successfully, but no sensor data was recorded.
Capture the telemetry that was missing from the first launch.
The flight computer successfully recorded sensor data during the flight.
The recorded IMU and altitude data were used to evaluate system behavior and confirm that the sensing and logging systems functioned properly in real flight conditions.
