Week 5

We were told to use Sbus but however we decided to ditch that idea as it was too troublesome as the Sbus signal has to go through a decoder into the pixhawk. So instead we decided to use PWM with a PPM encoder. As the encoder will combine 8 PWM channels into a single PPM wire. We also assembled the outer frame of the drone and assembled the motors and ESC. We also started researching on how all the components works together during assembly and what does each of the components do and how are we going to troubleshoot it when we encountered a fault.

The futaba receiver R2008SB has a built in encoder which allows us to connect to the pixhawk. This made connections easier. A power distribution board is needed to split the power to the rest of the system. This also cause minor problems when putting all the components together.

We tried prototyping a lever mechanism for the parachute release system. The parachute release system that uses electromagnets is too bulky for our drone so we moved on to building a lever mechanism. The lever mechanism is powered by a 12V, 1A linear solenoid which converts linear motion to rotary motion. The lever mechanism does not have sufficient force to open the cover of the parachute container due to shorter displacement done by the effort of the 1cm stroke solenoid than the displacement to open the parachute container cover.

Instead of using a lever, we decided to use linear motion by the solenoid without a lever to open the parachute container cover because there will be greater force to open the parachute container.