After two presentations at Bergtorpsskolan in Täby and two more at Naturvetargymnasiet in Södertälje the school visit part of our outreach plan is done for the time being. All work is now focused on the tasks that need to be finished for the Critical Design Review in the beginning of June!
One such task is choosing the proper streamer for the landing system.
In order to minimize the risk of the parachute getting entangled with the free-flying-unit (the ejected part of the experiment), it needs to be pulled out and away from it. We hope to be able to do this with a simple streamer, which is kind of like a long ribbon of cloth or plastic.
Streamers are commonly used on model rockets in place of parachutes, but we haven’t found any good info on them being used for anything bigger. This means we have to do some testing! What we’re mostly interested in is how the drag from the streamers varies with speed, the weight of the material, and the dimensions of the streamer itself.
This weekend I have a great opportunity to test just this my holding them out on a stick from a car, but first I need something to test! During lunch today I headed to a hobby store which just happened to have some streamers for model rockets at hand… including some big 7*70 inch ones!
The model rocket streamers are very light while the info we’ve found on the subject says that a heavier streamer might provide a lot more drag. However, thanks to the LAPLander team we have a lot of thick, heat- and tear-proof airbag cloth lying around at the lab, so I immediately got to work cutting out more streamers of various dimensions from that.
It’s going to be fun sitting in the back seat of a convertable testing all these during the weekend, I’ll write up a post about how it went next week!
Oh, and here’s a pic from one of the presentations we held at Bergtorpsskolan. It’s been great fun and the students have been really interested, and haven’t been afraid of asking us tricky questions! Hopefully we can go out and do this again after summer.
David and a group of students at Bergtorpsskolan