chunkulator
Joined: 27 Jul 2016
Posts: 219
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Managed to get my custom gas/ignition micro programmed up this evening as follows:
1. If gas is off and radio says turn on, switch on ignition immediately, pulse gas on for a short time (say 100ms) then turn gas off for a short time (say 100ms) for gas concentration to reduce to ignition point at sparker. Turn gas on again for main burn.
2. If radio says turn off, turn everything off.
3. If radio goes away (no PWM pulse for say 100ms), failsafe by switching gas off. Leave ignition on for about 1s to maximise the chance that any expelled gas has been burnt (you don't want a rogue robot sitting in an area full of unburnt propane). However, you don't want to approach the robot with the igniter running either - it's a taser and will give you a decent jolt.
I'm trying point 1 because I found that at full gas pressure the point at which the gas/air mix was right for ignition was way out in front of the robot. This meant I had to reduce gas pressure by turning down the gas tap to get it to ignite. However, what I want is to temporarily reduce gas pressure by pulsing the gas solenoid to achieve ignition and then burn at full pressure. It makes a pretty sick flame at full pressure!
Just got the firmware working, so over the next day or so I'll put the blowtorch back in the robot and give it a try.
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