Introduction
There is a lot more than meets the eye when rockets are launched into the air or space. In this case our hobbyist rockets undergo what is known as multi-level rocket separation. This means that the rocket separates into different parts at multiple stages in its flight path. The goal of this module is to provide interactive models and some multimedia presentations to educate elementary through middle school students with a passion for rocket ships and/or air and space engineering.
Rocket Parts
Fuselage Body
The fuselage body, also known as “body tube,” is the largest part of a rocket. Consisting of 2 hollow tubes that are connected with a coupler, a tube with a smaller diameter than the 2 hollow body tubes, that is inserted on an end of both tubes, that will allow the two to latch to the other. This is the main “shape” of the rocket and it is important to design an aerodynamic fuselage body so that the rocket can travel effectively through the air.
Shear Pin
There are two shear pins found on our hobbyist rockets. These pins are used to help hold the fuselage body together and protect the middle compartment from opening to release the parachute too early. They are designed to break apart when an external force is applied.
Bulkhead
A bulkhead is an impenetrable block that connects the two sections of the rocket together. They are found between the sections and usually protect a payload, in our case, a parachute to be deployed late in the flight stage of the rocket. Bulkheads are commonly made out of plastic, cardboard, or wood.
Eyebolt
The eyebolt is fastened to the bulkhead, and allows for the Shock-cord to be tied around the hook in order to connect the fuselage, bulkheads, and the parachute.
Bulkhead/Eyebolt Assembly
This assembly will be located inside of the fuselage body, this will connect the two ends of the rocket body together and allow for the parachute to be snug inside. On either end of this chamber there will be explosive powder ready to be primed to dislodge the shear pins and break the shock cord allowing for the rocket to separate and the parachute to be deployed.
Rocket
The above model represents what the rocket would look like when all the parts are put together. These parts all work together allow to the rocket to take flight and deploy parachutes when needed.
The rocket separation process is as follows: the Arduino circuit, or flight computer, is programmed beforehand to ignite a charge once the rocket reaches the desired height. This charge will create lots of pressure within the fuselage body that will force the shear pins to become dislodged allowing for the fuselage bottom and top to separate and deploy the parachute. The first parachute deployed is known as the “drogue” parachute. This parachute is very small and helps to stabilize the rocket during its descent. Once the rocket reaches a lower desired height, a second, main parachute is deployed that will allow the rocket to reach the ground safely.
Here is a graphical representation of when the rocket separation stages occur. Notice there are a total of two stages. In the first stage the drogue parachute is deployed. Then in the second stage the main parachute is deployed.
UF Rocket Team Examples
Drogue Ejection
As mentioned above, this is the first stage of the rocket separation, in a real flight situation the rocket would be at a high altitude and the rocket would separate into two parts and deploy the drogue parachute.
Main Parachute Ejection
This is the second stage of the rocket separation, in a real flight situation the rocket would be descended towards the ground and would deploy this parachute before landing to allow the rocket to land safely. At this point in time, the rocket will have been separated into three pieces.