It wasn’t that long ago that people were thinking that personal rocket jetpacks would be a reasonable means of transportation. Unfortunately, we’re still a bit of a ways off on that dream. That being said, we can still do a lot of cool things with rockets.
Rockets find their origins in ancient China. The availability of black powder to propel projectiles was a precursor to the development of the first solid rocket. The discovery of black powder by Ninth Century Chinese alchemists led to experiments in the form of weapons such as rocket-propelled fire arrows.
One of the earliest recorded devices that used rocket propulsion was the “ground-rat”, which was a type of firework. Fast-forward twelve-hundred years and you can find rocket technology still employed in weapons and fireworks, but where rocketry truly “took off” was in space technologies, particularly satellites, many of which impact people’s everyday lives in countless ways.
The basic principles of rocketry can be explored using a simple example. The trajectory of a simple rocket, as any first year engineer should be able to tell you, follows a parabolic arc. If you launch an actual rocket, it may not exactly follow that simple trajectory because there are a lot of external factors that can affect its path, weather conditions being the most important. Rocket manufacturers need to test how their rockets will react to different atmospheric conditions. In a recent application brief, you can see how a rocket is modeled using MapleSim. The model is broken down into subsystems modeling the rockets mass, thrust, altitude, velocity, and angle. Air density is also modeled and introduced as a random variable when calculating the drag experienced by the rocket. A Monte Carlo Simulation is run on the model with respect to changing atmospheric conditions, and the resulting trajectories are plotted. Having this information can now allow the user to determine the ideal conditions for launching the rocket, and what the expected trajectory should be.
Although a simple example, this model is quite useful in providing insight into the flight path of rockets. We may not have progressed much with the personal jet pack, but we’ve still done some pretty amazing things. Deviating from The Starland Vocal Band’s hit song, surely, it is more than an afternoon’s delight!