Build a CanSat

Step-by-Step

1. 1

   Plan your mission

   Define the objective: maximum altitude, sample rate, payload mass, recovery method. Keep the wet mass under ~350 g for safe recovery on a small parachute. Sketch the stack so everything fits inside the can with the battery at the bottom.

2. 2

   Wire up and bench-test the sensors

   On a breadboard, connect the Arduino to the BMP280 (I2C), GPS (UART) and SD card (SPI). Print one reading per second over serial for an hour to check for lockups. Verify GPS fix outdoors.

3. 3

   Build the flight software

   Write a single loop: sample → timestamp → write to SD → optional LoRa packet. Use a monotonic millis timer rather than delays to avoid drift. Store failures into a separate log file.

4. 4

   Transfer to a perfboard

   Lay out the perfboard compactly. Use wire-wrap or careful soldering; every gram counts. Secure the battery with Kapton tape and add a slide switch on the outside of the can.

5. 5

   Mechanical integration

   Drill or cut an access port in the can for the switch and serial/download. Pack foam to damp vibration. Attach a parachute via a swivel so it does not spin-lock the lines.

6. 6

   Range day

   Launch on a D- or E-class hobby rocket (or a weather balloon). Inspect the CanSat pre-flight, arm the switch at pad, log the serial output on recovery. Record ambient temperature for post-processing.

7. 7

   Post-flight analysis

   Plot altitude vs time and compare to your predicted profile. Look for dropouts in GPS (common under high-g) and fix the software or mounting for the next flight.