Awhile back J took an interest in science and, specifically, “star gazing”. AT Mom responded with an amazing art project that resulted in glow in the dark stars (arranged in real constellations) and 3-D glow in the dark planets hanging above J’s bed. (It really is a cool project.) AT Dad, on the other hand, responded by rewiring the launch controller for a model rocket to be switch activated.
NOTE: Since the launch controller includes safety mechanisms to prevent unintended launches and rewiring the controller needs to be done in a way to not bypass these safety mechanisms, I will not be describing how to rewire the controller. Consider this post as inspiration for what can be switch adapted. If you have the technical knowledge of circuitry the rewiring is not difficult; however, it is easy to get wrong resulting in unintended launches. (Which you will find out happened to me this initial attempt.)
This is an AT project that was stretched over a number of weeks. Most of that time was just waiting for the time to build the model rocket together and then waiting for a good launch opportunity. (Our first two planned launches were cancelled due to rain.)
The project started with a trip to the local hobby store. J and I went up and down the aisles looking for a science related project for home. I would take something off the shelf (take a quick look to make sure I had an idea of how J would participate) and then ask J if it was something J wanted to try. We tried various science kits (solar car, potato clock, etc.), electric trains (which I was hoping for since I had some cool ideas for connecting a train set to J’s eye gaze system), and a few others. Finally, I offered a model rocket and J’s face lit up. We had our science project!
Before purchasing the kit I talked with the guy at the hobby store. He gave me some great ideas about launch locations and informed me about local model rocket clubs / associations. I asked about switch adapting the launch controller. I got the response I expected, a confused look followed by something like “that sounds cool.” Since the launcher worked by pressing a button I was highly confident I could put a switch connector in parallel to the button, so we bought the kit and headed home.
A few weeks passed, ever so often I would take out the model rocket kit and imagine J pressing a switch to launch the rocket. I got some time to focus on the launch controller and began to take it apart. I actually had to get out the Dremel and cut away some of the plastic to get at the circuitry. It took a little finesse but I got the launcher working the way I thought it should (I was not going to connect it to an engine until launch day).
Later that week J and I found some time to actually construct the Taser model rocket. J helped me follow the directions and showed me with eye pointing where the different parts went together. When the rocket and launch pad were fully constructed (and all glue was dried), J and I set it up on the floor and simulated a few launches (AT Dad lifting the rocket up the launch post).
A few more weeks passed, every so often J and I would excitedly simulate a couple of launches in the house. We planned on a Friday afternoon launch, but were foiled by a summer rain. Not big rain, but enough to make me pull the launch for that day. I told J we were official rocket scientists now because we had a launch scrubbed by weather.
We rescheduled the launch for the following Friday afternoon. But a week later we were foiled by another light rain. So another couple of weeks needed to pass before our next launch window.
Then came a beautiful Thursday afternoon (I wasn’t going to tempt another Friday afternoon ). J, J’s Papa, and I headed out to a local sports field complex for the launch. I set up the launch pad, inserted the engine into the rocket, slid it onto the launch pad, connected the launch controller to the rocket, connected J’s switch to the launch controller, inserted and depressed the safety key (arming the launch controller), told J to press the switch when ready, J pressed the switch, and ….
I removed the safety key and disconnected J’s switch from the launch controller. Checking everything I found one of the alligator clips had disconnected from the rocket engine. I reconnected the alligator clip, reconnected J’s switch, inserted and depressed the safety key (arming the launch controller), told J to press the switch when ready, J pressed the switch, and ….
I removed the safety key and disconnected J’s switch from the launch controller. Checking everything I found that the primer was broken so it could not start the engine. I inserted a new primer into the engine, reconnected the alligator clip, reconnected J’s switch, inserted and depressed the safety key (arming the launch controller), FFFFFFFFFFFFFISSSSSSSSSSSSSSSSSSSSSSSHHHHHHHH!
The rocket launched when I pressed the safety key. This should have only armed the launch controller. We watched the rocket fly a couple hundred feet up before deploying its parachute and floating back to the ground. I turned and asked J if that was neat and did J see the rocket. Then I turned my attention to the launch controller. I deduced that in my rewiring of the controller I unintentionally created a short that fully closed the circuit when depressing the safety key.
We had one more primer and two more engines, so we could do one more launch. I retrieved the rocket, repacked the parachute, inserted the engine into the rocket, slid it onto the launch pad, connected the launch controller to the rocket, connected J’s switch to the launch controller, inserted the safety key (but did not depress it yet), told J to press the switch when ready, J pressed the switch (and I depressed the safety key at the same time), and ….
A second successful launch! I asked J how J liked the rocket. J smiled. I learned a couple of things that I will change for next time (and there will be a next time). First, I need to get another launch controller and do a better job of rewiring it. If I cannot do a better job of rewiring an existing controller, I will have to construct my own from scratch. Second, prior to launch I will tilt J’s chair back to full tilt – making it easier for J to watch the rocket fly above us. Third, for the class of engine I used I now know I can get away with a launch area of two soccer fields wide (given a relatively calm wind).
When I do have a follow up launch, I will make sure to share the details of that experience and provide select details from my (hopefully) successful adaptation of a rocket launch controller.