The summer feels over, but despite some shock showers on Monday the space was open. Adrian took the clock we were given by Nottinghack (couriered by Martin) and with Mat started writing up what they found inside. A number of repairs were performed by a few different people, fixing a bicycle inner tube, a DVM, and the identification of a car part for order.
We also discussed what events we could run at meetings. Some suggestions:
- Nanode workshop
- Photography (light painting)
- Kinect hacking
- Revisiting OpenCV hacking
The idea is for very limited scope projects that allow a sense of accomplishment within a few hours. Suggestions are welcome on the mailing list.
Date of next meeting: 19th September from 7pm
Despite some initially poor weather, it dried out, brightened up, and the wind died down to allow us to launch some stuff! Check the flickr feed here. For those interested in the telemetry data from the payload we sent up, it looks like this.
Quite a short run as the rocket didn’t take long going up or down. Acceleration data isn’t terribly readable – the peak acceleration is obviously off the +- 4g scale of the accelerometer.
One bad data point on the pressure causes the smoothed graph to have a small dip in it, but otherwise the data appears consistent (if unverified).
Temperature data isn’t useful, the sensor is cooling from a previous high of 35C from being wedged into the rocket nose cone.
Mat’s plane made a couple of trips up and down and around. The temperature data again doesn’t appear to useful, as the sensor is much less responsive than the barometric one (they’re in the same package). Currently it’s not used for altitude calculations.
We’ve fleshed out (a little) the plans for the ballistics day for this year. It will be held in Delapre Park, hopefully very close to the NSME facilities (inside the park, next to London Rd). If fate intervenes and we need to be further away, we will mark up on the NSME gates where we are, for ease of navigation in the park.
We’ll start gathering at 11am, but will not be aiming to launch anything before midday. So if you’re coming to watch, you don’t have to be present from the very beginning. We’ll run until we get bored, which will be 4pm at the earliest. In case of (mild) rain we’ll have a marquee and the NSME clubhouse will be available in dire emergencies. It has toilets, and a water supply for the filling of water rockets, so you don’t need to bring litres of water with you.
The firing range will be marked off with traffic cones and rope. This is not an insurmountable barrier, particularly not children or toddlers, so if you bring children it is very important that you do not let them cross the ropes when someone is launching. Also, unless you’re launching something, you should not cross the ropes either.
Please bring your own rockets and tennis-ball launching devices, and launch with us! If you want to make a water rocket, use a plastic bottle from a fizzy drink and add fins, nosecone, and anything else you like with card or cardboard. Why not turn the afternoon into a picnic and bring food and a blanket? You might even be able to launch your drinks bottle!
We had a (very small) meeting this week, which mainly consisted of planning the Ballistics Day (details in a second post). I also attended the NSME committee meeting and that was also productive:
- If we start supplying bracket specifications to the NSME someone will produce the resulting brackets, possibly producing cardboard ones first to check fit. We’ve agreed doing one axis at a time would make sense. If the mill is useful to the club they would then consider purchasing the parts that are still Martin’s. If the endeavour fails or is unused by the club then Martin’s parts can be given back, and the rest sold.
- A marquee will be left in the clubhouse for use if required on the Ballistics Day. There is also a water supply and hose for steam trains and water rockets which we can use.
- The NSME are impressed with our railway clock, but do not desire one of their own, as it would not be in keeping with the station’s aesthetic.
Alan gave a very interesting talk on Stirling Engines, and buoyed by his information that they’re very simple and have few moving parts, we tried to make one.
Surprisingly, this didn’t work, possibly due to:
- Poor tolerances
- Wrong materials (it’s supposed to be a steel can for a better temperature differential)
- High mechanical friction
In other news, the Ballistics Day approaches, 6th August. A poster is being prepared, and will be posted on here shortly.