Condor Logbook

Entry 1: Discussion about the secondary mission

What we did:

Brainstorming of ideas:
  • A cansat that would scan the Earth's surface and then using ai it would reconstruct it in 3D
  • A cansat whose flight could be controlled and optionally it would scan the surface
  • A CanSat that would act as a rover after landing, take pictures and explore the environment
  • A cansat that would have a controlled and safe landing
  • A cansat that would extend wings to achieve controlled flight
Outline of the approximate dates and things we need to do

Entry 2: Determining what our secondary mission will be

  • We chose to make a CanSat that will have a controlled flight using a ram-air parachute
  • Proof of concept that such a small device/satellite could be controlled using only two servos and potentially one dc motor
  • Further brainstorming of design

Entry 3: Getting more accustomed with the CanSat requirements and deadlines

  • We found out that there is a minimum descending speed (5 m/s) which slightly altered our design
  • Discussion about picking parts, so that we meet the requirements for the first deadline
  • We will also need to consider the protocol we want to use:
    • ELRS
    • mLRS
    • WiFi

We will need these parts: receiver, transmitter, flight controller, computer for ground station

Entry 4: More specific identification of parts that we will use

Parts:

  • We determined that mLRS will be the ideal protocol for us since it meets all of our requirements (long distance, telemetry, rx transmission), and it is also quite well documented
  • Receiver: Matek mR900-30 mLRS 868MHz RX
  • Transmitter: Matek mR900-30-TX mLRS 868MHz TX Kit

We also determined that we will use the raspberry pi 4 as the ground station:

  • Has the necessary computational power for our use case
  • Has the pins that will be required to set up the transmission

We still need to choose a flight controller

Entry 5: Picking the SpeedyBee F405 Wing Mini

We chose the SpeedyBee F405 Wing Mini flight controller because:

  • It has a sufficient amount of output pins that will be necessary to control the servos
  • It already has some built in sensors that we will need to use
  • It has all of the needed connectors to connect our sensors (GPS, compass, temperature)
  • It is in stock in the Czech Republic
  • It is relatively compact

Ordering of parts:

  • We ordered: Matek mR900-30 mLRS 868MHz RX, Matek mR900-30-TX mLRS 868MHz TX Kit, SpeedyBee F405 Wing Mini

Discussion about the publicity of our mission:

Entry 6: Sketching the wiring diagram to determine the requirements for the flight controller

Entry 7: First assembly of parts to check compatibility


Determining what antenna we will use on the ground station that meets these requirements:

  • Dipole antenna
  • Directional: Moxon
  • Operates within 900/868 MHz

Entry 8: Purchasing the antenna

We decided to go for a directional antenna. The specific model is Radiomaster Bandit Moxon 868/915MHz because of its reach and a relatively price.

Entry 9: Testing the reach of the connection

We decided to test in the Centrální Park near the Opatov station as it was a convenient location. The connection was stable and reached a distance of about 1000m through obstructions. As it was too cold, our hands began to freeze and we had to halt testing.