This is my new project, containing a cluster model rocket with integrated mini DV camcorder and a Picaxe based rocket launch controller with 2 digit 7 segment display.
Sor far I have finished the launch controller. Circuit diagram and program attached. The displayed time before ignition can be adjusted between 0 and 99 seconds by pressing alternately one of the two push buttons (plus, minus). If the two push buttons are pressed at the same time, the countdown starts. A LED indicates if the the igniter is properly connected to the terminal block.
The rocket is a 2 engines cluster kit, called Gravity Rider. I like this rocket, because it looks not like a common rocket. I have built the rocket already but have not finished the paint job, chute etc.
The camera (720 x 480 dpi with a 16 GB micro SD card) is from the Chinse Ebay called taobao:
I have also derived some important rocket equations with air drag. If somebody wants to dig deeper into rocket science, please see attachment. Maybe I will use the equations later to write an own simulation program or use it for an advanced flight computer.
2010.11.28
Rocket finished but windy and rainy weather here in Shanghai :(
Rocket launched but onboard camera had a malfunction. Tests on dismantled camera showed that the camera has an internal short circuit, probably caused by the acceleration and vibration of the rocket.
2010.12.18
New rocket cam test by my colleague Mattias from Beijing.
He used a mini DV HD camcorder on a RTF model rocket with a modified objective:
Awesome, How did you derive your asymmetric design? I understand you had to compensate for a camera that was not centered, but how did you arrive at your design, and did it fly straight? It’s a little hard to tell from the video. Is the small hollow tube for air stabilization?
I was surprised at how stable the video from the “going up” flight was.
Was that a purchased engine or the fruits of your hexamine experiments?
I agree with Frits too, high tension power lines are just evil !
I have some theories why it not works, but can not proof it as my laboratory has not the required equipment.
The sound of the second rocket launch is awful. It’s no frog, mouse or alian. I guess the exposed microphone was in contact with the body tube of the rocket and all vibration were transformed into (scary) sound.
And because the creepy sound is for nothing, I will use the audio input of the camera as a kind of data logger for my next rocket project (principle Commodore Datasette). I probably will build an altimeter with a micro controller and a Motorola MPX4115A pressure sensor. Frequency change with altitude change. Stay tuned