R C Circuit with 3 specific output parameters, and specific physical
R C Circuit with 3 specific output parameters, and specific physical
(OP)
http ://files.e ngineering .com/getfi le.aspx?fo lder=fde41 c28-82d2-4 b7a-a194-c 07501bf759 9&file =Circuit_p roblem.pdf
Hello , I have included my best efforts at a schematic, and related formulas for my problem as an attachment to this post. Please take a look at it if you have the time.
My requirements are to produce 2 volts, and 13 amps, for 30-40 Milliseconds.
My constraints are
* a very minimal physical presence in terms of weight, I have 3 ohm resistors I need the requirements passed through in parallel ( I think they need to be in parallel, to receive the requirements simultaneously, simultaneity is a constraint)
* the power source must be physically disconnected for at least 20 seconds before the requirements are delivered to the resistors.
My variables are
* Just about any power source financially accessible less than a car battery ( expense )
capacitor Farad value can vary
Additional resistors or small lightweight components can Vary, (lightweight in the grams magnitude)
wire gauge has to stay pretty small
I've tried to model the probem myself by thinking about the Time constant in the V(t) = V(o)e^-(t/RC) equation, but I find that the one ohm resistors force the time constant into the nearly instantaneous condition, whereas I need 30-40 MS.
I have been stumped by this problem for months, and have asked many people, I wouldbe very impressed to find a nice elegant solution, and EXTREMELY appreciative. If you would like to reach me directly my email is joexsmurf@gmail.com I will check the forums often for a response.
Thank you for your time.
http ://files.e ngineering .com/getfi le.aspx?fo lder=fde41 c28-82d2-4 b7a-a194-c 07501bf759 9&file =Circuit_p roblem.pdf
Hello , I have included my best efforts at a schematic, and related formulas for my problem as an attachment to this post. Please take a look at it if you have the time.
My requirements are to produce 2 volts, and 13 amps, for 30-40 Milliseconds.
My constraints are
* a very minimal physical presence in terms of weight, I have 3 ohm resistors I need the requirements passed through in parallel ( I think they need to be in parallel, to receive the requirements simultaneously, simultaneity is a constraint)
* the power source must be physically disconnected for at least 20 seconds before the requirements are delivered to the resistors.
My variables are
* Just about any power source financially accessible less than a car battery ( expense )
capacitor Farad value can vary
Additional resistors or small lightweight components can Vary, (lightweight in the grams magnitude)
wire gauge has to stay pretty small
I've tried to model the probem myself by thinking about the Time constant in the V(t) = V(o)e^-(t/RC) equation, but I find that the one ohm resistors force the time constant into the nearly instantaneous condition, whereas I need 30-40 MS.
I have been stumped by this problem for months, and have asked many people, I wouldbe very impressed to find a nice elegant solution, and EXTREMELY appreciative. If you would like to reach me directly my email is joexsmurf@gmail.com I will check the forums often for a response.
Thank you for your time.
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RE: R C Circuit with 3 specific output parameters, and specific physical
TTFN
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Chinese prisoner wins Nobel Peace Prize
RE: R C Circuit with 3 specific output parameters, and specific physical
I am not a student. That's kind of a rash assumption. I am a Civil Engineer, I do structural design engineering. I also do model rocketry for a hobby. My goal with this circuit is to charge a capacitor on the ground that will discharge at a certain moment in flight. That moment is after the first booster has burnt out, but instead of lighting just one additional engine after that, I want to light 3.
The problem has 3 aspects..
-Simultaneous firing.
-no battery going up ( too heavy)
-Firing has to be timed, this will be done physically triggered by the seperation of the lower stage.
Anyway, hopefully someone else has a more productive response.
RE: R C Circuit with 3 specific output parameters, and specific physical
A much better approach is to use a small hearing aid or clock battery. They can easily do what you want. Switch control is a separate issue. Get the available power right first.
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: R C Circuit with 3 specific output parameters, and specific physical
Thanks for the reply, I have purchased a small hearing aid batteries that seemed rated in voltage and amperage to what I need. However this is a path I'm reluctant to use, even though 3 batteries of that size are not much more weight than the capacitor, it would mean having to change the batteries by deconstructing and reconstructing the rocket. Vs if I use the capacitor solution, I can just use any battery source outside the model, and replace it as I need to without deconstruction.
However I think I understand what you are saying about the energy being minimal, is there no way to modify this by using different capacitors, resistors, or any other circuitry ?
RE: R C Circuit with 3 specific output parameters, and specific physical
I cannot see any problem with that battery. Wires to a batteri compartment that is accessible from outside. That is how it is done.
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: R C Circuit with 3 specific output parameters, and specific physical
* http://www.cap-xx.com/products/products.php
e.g. GS2
RE: R C Circuit with 3 specific output parameters, and specific physical
Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
RE: R C Circuit with 3 specific output parameters, and specific physical
RE: R C Circuit with 3 specific output parameters, and specific physical
The specified load has only 154-ohm resistance, so circuit parasitic resistance options are very limited. Even the specified 40 mohm ESR will drop 0.5V at specified output current.
TTFN
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Chinese prisoner wins Nobel Peace Prize
RE: R C Circuit with 3 specific output parameters, and specific physical
Another option would be to separate the three circuits into three separate loops. This would drop the current and make things a bit easier. It's unusual, but I think one could still use just one high current switch to close all three circuits at once (provided they're all at the same state of charge). The reduced current in each loop might bring little batteries (x3) back into the realm of possibilities.
RE: R C Circuit with 3 specific output parameters, and specific physical
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
Chinese prisoner wins Nobel Peace Prize