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.

Thursday, March 31, 2011

Servo Timer II test flights

This weekend we went down to the local park to start the Servo Timer II trial flights. We flew a total of 7 flights with the timer and thankfully all worked well. Two of the flights included the uMAD for triggering the timer at apogee.

The full launch report along with a highlights video is here:

We are now preparing larger rockets to continue the tests. We would like to do an additional 10-15 more flights before starting a production run of the timers. Yesterday I was going to do some tests with one of the timers, and noticed that I had left the power switch ON, and completely drained the battery over the last few days. So this morning I updated the firmware to flash the LED briefly every 5 seconds to remind me to turn the power off.

Monday, March 28, 2011

Website Issues

We host our website with GoDaddy, but it looks like they have been having some issues over the last couple of days. It was up briefly yesterday, but it looks like they are having issues again today. Lots of people are reporting the same problems as well. Hopefully the website will be up again soon.

Monday, March 21, 2011

Wet but productive weekend

Unfortunately we didn't get to test fly the servo timers this weekend as it pretty much rained both days. We had over 100mm at our place. So it was a good time to spend in the workshop. We are trying to build up our inventory of spare parts so we can focus on flying rather than fixing. I'm also trying to get components ready for rockets to fly at Williams later this year.

We are making a big run of spliced quads at the moment that will be fiberglassed, both 90mm and 110mm. This weekend we cleaned, cut, shrank and curled some 70 bottles.

Here they have been shrunk and are ready to be curled.

After curling they have been paired up ready for sanding and gluing. This should give us about 10 x 110mm quads and about 11 x 90mm quads.

We also fiberglassed two more 110mm spliced quads yesterday. These will be used as spares on the flight day of G2. We have 6 of these now, with 4 of them still needing to be pressure tested to 270psi. Some of the fiberglassed 90mm spliced quads are going to be used in Acceleron V's sustainer. I'm looking forward to this flight as it will be our first dual pressure launch.

We also made a new 90mm nosecone with the Servo Timer II which uses the small LiPo batteries. This new nosecone including the fairing it sits on weighs in at 86 grams. Our regular nosecones weigh around 154 grams. The nosecone also uses a new ejection plate mechanism that has more force to get the parachute out. I'll post details and photos with the next web page update. We are using the same technique for ejecting the G2's backup parachute.

We are currently planning to launch the G2 with just 3 spliced quads (~15L) on the first flight, just in case the rocket again decides to drill a fence post hole. If the first flight goes OK, then we will screw in the fourth bottle and launch again.

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.

Sunday, March 06, 2011

Panorama tutorial

I've uploaded a tutorial on how to make panoramic images from on-board rocket videos taken with small cameras such as the 808 keychain or MD80 clone.

It requires you to have Photoshop, and VirtualDub (which is free).

Thursday, March 03, 2011

ServoTimer II prototype

In the last couple of days I've soldered up the first prototype of the ServoTimer II.

 Top and bottom view of the timer

 Here it is next to V1.6 of the flight computer

I finally, got it running and bench tested tonight. I'll make up a couple more in the upcoming days and then fit them in deployment mechanisms and test fly them quite a few times. If all goes well, then I'll get actual boards made by a PCB manufacturer.

All up it weighs ~6 grams with the battery clip adding another 2 grams.

Tuesday, March 01, 2011

Foam flights

This weekend we went to the NSWRA launch event again, but because we didn't have the Polaron G2 rocket quite ready yet, we just flew smaller rockets. These were basically assembled the night before launch out of spare components. The update is here along with a highlights video: