Hello
I want to make a recovery system for my model rocket to send electricity to the black powder's container and then explode it to eject the parachute.
I want to use Arduino UNO for my model rocket. how can i do this ?
Should i use else components or modules added in my arduino ?
You can, but if your rocket is not extra powerfull, then the uno will most likely be too heavy.
Use a logic level MOSFET to switch the high current to the ingniter. An Arduino output is only good for a recommended maximum current of 20mA.
And i agrees that the Uno is less suited for your application than, say, a Nano or Micro.
A bare-bones Attiny 45 might be sufficient and a great deal smaller and lighter.
...R
The beginner's guide to millis() tutorial has good information on using millis() for timing.
I would expect government officials to start showing up on door steps if we get too far into programming “hobby” rockets into smart rockets.
Slumpert:
I would expect government officials to start showing up on door steps if we get too far into programming “hobby” rockets into smart rockets.
Sounds like the right counterbalance to all the rest of us who have been throwing up in the face of Government "smart rockets" 
At least the hobby rockets won't have nuclear warheads.
...R
... but we could work on that, remember the "radioactive boyscout" ...
zwieblum:
... but we could work on that, remember the "radioactive boyscout" ...
No. But I still have my tinfoil hat somewhere.
...R
Thanks to all.
I found that we can use relay module on arduino to do this job.
Is this right ?
Kianoush:
I found that we can use relay module on arduino to do this job.
Is this right ?
How big is the rocket?
A relay is a very heavy thing compared to a MOSFET.
...R
I'd suggst you buld the rocket just a little bigger and add a trained ape.
zwieblum:
I'd suggst you buld the rocket just a little bigger and add a trained ape.
I can't agree with that. If you want to go down that route make it big enough for a human.
...R
The rocket is very big, it is about 10 feet long and 40 kilograms solid fuel
Actually it is a university project.
Kianoush:
The rocket is very big, it is about 10 feet long and 40 kilograms solid fuel
Even so I suspect both Nasa and ESA would be sufficiently weight conscious to need a lot of convincing to use a relay where a transistor would appear to be sufficient.
What if the take-off acceleration was sufficient to cause the relay contacts to close?
...R
I would not use a hobby grade relay.
The G- forces would likely trigger a premature....
Slumpert:
I would not use a hobby grade relay.
The purpose of my comment was to see if the OP had considered the effect of rocket forces on components.
...R
Why should he? It's part of the learing experience! (and now you have pulled out the fun of the project)