Aerobraking System

We did some research into how we could minimise the speed at the final descent and

we decided to go for an aerobrake system. We aimed to shed most of the mass during the final descent and generate as much as lift as possible, with the aim to prolong the flight for the final stage of descent (i.e. 10 metres off the ground). We decided to deploy sails that would be released by the main parachute system.

The initial calculated aerobrake had shown that the initial deploying of the break worked how we had intended (Figure 23). We dropped the test with and without the sail and noticed a decrease in the descent velocity. But we felt we could make it more efficient and reduce the velocity even more.

Increasing the surface area of the aerobrake system

We decided to extend the arm for the sails, by creating a hinge in the arm that would be stowed inside the CanSat. From the image above, it can be seen this more than doubled the surface area for the aerobrake system.

During the drop test of the modified aerobrake system, we noticed the aerobrake system was working better, but since it was now generate more upward force, this was creating a moment and the CanSat was rotating during the descent. This was due to the centre of gravity be located closer to the top.

Testing with lower centre of gravity position

We decided to add a few hundred grams to the bottom of the 3D print to reduce rotation, but in turn caused the arms to break since the 3D print was hollow. We then created another 3D print which had stronger and more solid arms which are not as fragile. This improved the survival chances of the CanSat. We added fishing lines at the end of the arms to the bottom of the CanSat to stop the arms rotating and distributing the force. We decided that was now our final design and we would focus on refining the CanSat with more drop tests and only minor modification before the regional event.