Hello!
- Thread starter akwertyy
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Are you guys looking into a fully wireless launch controller for the first stage on the ground, or ignition of an upper-stage/airstart motor without a direct physical connection between the stages? You’re going to get different answers for the two.
We're looking to do a wireless ignition of an electric igniter on the ground. Basically what this guy was trying to do () but with two rc relays instead of just one for redundancy/safety reasons. The rc relays we used: https://shorturl.at/bgqWY. Data sheet for the relays here: https://shorturl.at/ipu59. Schematic below (the led symbol is where the match would be). The plan was that the relays would be mapped to separate buttons, so that in order for the match to ignite, both of the buttons would have to be pressed at the same time. In this scenario, we had the relays set to be normally open.
Instead, what we have found is that neither of the relays function when both buttons are pressed. We think that the issue is that there's signal interference, since both of the relays operate at a frequency of 433 MHz.
Right now we're looking at if there's any way to resolve this, such as if there are other relays available for consumers that don't operate at a frequency of 433 MHz. We're also looking at other alternatives.
Instead, what we have found is that neither of the relays function when both buttons are pressed. We think that the issue is that there's signal interference, since both of the relays operate at a frequency of 433 MHz.
Right now we're looking at if there's any way to resolve this, such as if there are other relays available for consumers that don't operate at a frequency of 433 MHz. We're also looking at other alternatives.
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I see.
I cannot diagnose your failure, but I’d say interference sounds like a likely candidate.
Just a bit of background info and couple questions about your design process:
Most commercial and homemade launch controllers, wired or wireless, use a key and button arrangement for safety. Often the key circuit is connected to an audible buzzer and continuity light to indicate that the pad is armed, and a single button fires the igniter. The igniter will not go while the key is out, or not turned (“Turn your key, sir!”
).
Many high-power clubs have a band of switches to support a whole rack of rockets going either singly or multiply.
Was a design of this sort considered as part of the design process? If so, why was it rejected?
Is a wireless system a better fit for the team’s needs than a wired one?
I cannot diagnose your failure, but I’d say interference sounds like a likely candidate.
Just a bit of background info and couple questions about your design process:
Most commercial and homemade launch controllers, wired or wireless, use a key and button arrangement for safety. Often the key circuit is connected to an audible buzzer and continuity light to indicate that the pad is armed, and a single button fires the igniter. The igniter will not go while the key is out, or not turned (“Turn your key, sir!”
).Many high-power clubs have a band of switches to support a whole rack of rockets going either singly or multiply.
Was a design of this sort considered as part of the design process? If so, why was it rejected?
Is a wireless system a better fit for the team’s needs than a wired one?
I see.
I cannot diagnose your failure, but I’d say interference sounds like a likely candidate.
Just a bit of background info and couple questions about your design process:
Most commercial and homemade launch controllers, wired or wireless, use a key and button arrangement for safety. Often the key circuit is connected to an audible buzzer and continuity light to indicate that the pad is armed, and a single button fires the igniter. The igniter will not go while the key is out, or not turned (“Turn your key, sir!”
Many high-power clubs have a band of switches to support a whole rack of rockets going either singly or multiply.
Was a design of this sort considered as part of the design process? If so, why was it rejected?
Is a wireless system a better fit for the team’s needs than a wired one?
The previous wired version also used a two momentary button arrangement. Like I said, I'm pretty new to the team, so I don't know if the key and button system was previously considered, but I can bring it up with the other people on my team. As for the wireless system vs wired system, the team is currently trying to make the transition to the former because it would be more convenient compared to spooling out 100 hundred feet of wire and then respooling it, especially under cold conditions.
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