Recent content by Wetmelon

I.e back emf protection? No problem

Thanks for the continued support, BigGuy, it is appreciated! Ah yes, I have been neglecting the cable resistances. Good catch. Roughly, yeah. Precisely. Simply because I don't want to burn out the FETs and to help save the battery. This would be very helpful, yes. Test battery is a 3 cell...

Apologies, the "max all-fire current" is the current at which the igniter/load, which is a piece of nichrome wire coated in gunpowder, will always ignite. The actual highest "detection" current that we can use is going to be around 70mA. Also, most other model rocket engine igniters are much...

It oscillates during a short in the sense that the logic would turn the PFET off, then get pulled up, turn the PFET back on, turn it off, get pulled up, turn it on, etc. Basically I'm trying to drive the 1.77Ω load, which is a "Quest Q2G2 Model Rocket Igniter". The igniter burns and...

When the fet turns on, it's expected that the 1.77Ω resistor explodes into a nice flame (70+ watts). If it creates an open circuit, great! If the leads create a short, it would then oscillate. See my edit for more info.

How to prevent a circuit from "cycling" / oscillating Hello everyone, I have the following circuit I designed. Although I am open to all criticisms and suggestions, my main question is thus: If the resistor 1.77Ω (load) becomes a dead short when the highlighted momentary switch is closed...

Sorry i didn't get back to you. I was thinking along the same lines as rbelli above me though, that somehow you're not saturating the fet. Maybe the chip floats a small voltage for some reason? Shouldn't but you never know...

What's your voltage across the mosfet when it's Off? Is it actually 3.3? Are you sure? I will preface this by saying I'm not an engineer I'm only a student, but as I understand it it is inadvisable to drive ground connected loads with an n channel.

So the gyroscopes don't measure velocity? What do they output? Rotation angle?

I am designing a motion tracking device and just discovered that there exists solid-state gyroscopes. My question is simply "What is the benefit or application of the MEMS Gyroscope compared with a solid state accelerometer?" As far as I can tell, the accelerometer and the gyroscope can be...

Oooo. I thought it was an insulative t-shirt (because they have to keep them dry). I've never actually looked into how the current system functions all that much, do you have any resources you were able to find?

The olympic fencers use this method for their wireless technology, if i understand what you're saying correctly. Essentially it uses the body's natural capacitance to detect closed circuits. There are also RF designs that have been explored and work quite well, though I'm not sure what the...

Actually, in the period since i posted this, I though perhaps extruding the plastic, rounding the end, then cutting to length would be more effective. Any thoughts? Note that the pellet is 6mm diameter (approx)

I managed to get the proper Flow Simulation software going; the good stuff. As I have it (The full pellet), I'm generating about 1.525e^-5 Nm of torque, giving me an angular acceleration of about 200,000RPM/s. This might be adequate, but it's hard to tell. I'll have to get some actual fired...

The end result I'm looking for is the object's stability through air (at about 100-150m/s) along its longitudinal axis (i.e. no yaw or pitch deviations). I assume this means an adequately high rotational speed I'm just using FloXpress in SolidWorks, so I'm not sure about how much capability...