Here are some more details on the rocket I am building.
The entire system is custom fabricated by myself. I have been building KNSU (Potassium Nitrate / Sucrose in a 65/35 ratio) propellant engines. To date I have launched a lot of small 25mm PVC engines, a lot more fun (and altitude) than the small Estes kit my brother paid over $100 for. I am in the process of building, refining and static testing a 40mm KNSU engine for use to launch my first generation PVC rocket.
The first generation rocket will last for a single flight as there will be no recovery system, it is mainly to verify the engine and my basic rocket building skills. Obviously no onboard electronics for this one. It consists of a 220mm long fin/engine section made from 50mm PVC pipe left-over from a plumbing job I done around my house. This fits into a body section 400mm long empty section of 50mm PVC, A 100mm long nose cone slots into the body section. There are four trapezoidal shape fins, laser cut from 3mm acrylic sheet (the upside of working for an engineering company is I can use the laser cutter whenever I want for free!)
The second generation rocket will be similar to the first, but this time with a single parachute recovery system to test the parachute and deployment system design. There will only be a basic 555 timer based deployment electronics to fire the deployment charge. If the rocket is recovered intact, I will have a second motor and deployment charge on standby to do an immediate re-load and re-launch to test re-usability.
The third generation rocket will have a larger engine, a drogue & main chute recovery system, which will be controlled by the flight computer (the FEZ will be in charge here). It is planned that upon detecting apogee, the drogue chute will deploy, allowing a quick but controlled descent, and once the computer is a preset distance above the ground, the main chute will deploy slowing the descent further, this way, the rocket will fall quick enough to keep the rocket close to the launch site, but still allow a soft landing under chute.
My eventual aim is to get to an altitude where the on board cameras will record both the curvature of the earth below it, and the blackness of space above it. And the biggest kick I will get from all this is knowing it was all my own work that got me there, no “off-the-shelf” components.
With the FEZ based flight computer, the design will also progress in three stages. The first is on a breadboard with the breakout components, in order to quickly refine the hardware and write the software.
Stage two is taking the breadboard design and packing it into the rocket using stripboard as a breadboard substitute, testing it in-flight.
Stage Three is designing as small a PCB as physically possible and soldering a computer together in the final configuration, and building a dedicated “avionics bay” section I can slot into the rocket body for flight.
I will be documenting Stage One of this process, and possibly (depending on interest) making available finished Stage Three boards to anyone who wants one.
