This blog covers the day to day progress of water rocket development by the Air Command Water Rockets team. It is also a facility for people to provide feedback and ask questions.

Monday, March 07, 2011

ServoTimer II video

I've posted a video on YouTube of the Servo Timer II prototype in operation. The video shows the normal operation, configuration, as well as how to interface it to external sensors like the magnetic apogee detector (MAD) from Whooshtronics. It also shows how you can chain the timers together for driving multiple servo motors for things like staging and parachute deployment, or drogue/main parachute functionality.


Anonymous said...


As a thought - to get more bang for your buck in a water rocket - would adding sugar to the water inside the rocket assist? ie a strong sugar solution (harmless) seems to have a density of 1.4grams per litre - or an extra 40% weight, therefore notably more power?


George Katz said...

Hi Charlie,

Actually it's the other way round. You want a less dense liquid in your rocket. While it's true that you are expelling a heavier liquid resulting in higher thrust, however, you are also having to accelerate a heavier mass (sugar and water) still inside the rocket.

If you have a look a Clifford's simulation, try entering in a different water density value and you'll see how that affects performance. Make sure when you run the sims, you give a range of values for the water amount, as different densities have different optimum volumes. You'll see that lower density liquids give better performance (altitude) than higher density ones.

So how do you get a lower density water without using some more expensive liquid like alcohol? .... you aerate it. :)