Nick,
The force from a spring (or a rubber band) is a function of the
distance it is stretched. In a wound rubber band, the distance it is
stretched depends on its unstretched length and the number of turns.
So, with a half motor stretched half the length of a full motor and
half as many turns, the force should be approximately equal. If
rubber bands follow Hooke's law, it will be perfectly equal. However,
I doubt that they do. With a scale and some careful measurements, you
could make a mathematical model for the force. So from all this, the
conclusion I draw is that the only difference with half motors is that
all times are half of what a full motor would provide. By times I
mean the total duration, how long it climbs, how long it cruisies,
etc. Of course, this assumes a perfect motor, and no other odd
"real-world" things.
Nicholas Huang
Boise, ID
--- In Indoor_Construction_at_yahoogroups.com, "Nick Ray" <lasray@...> wrote:
>
> John,
> Your assertion is correct. The theory that is currently held by the
> majority of indoor fliers states that if everything thing is done
> properly they results will simply be a scaled down version of the full
> flight. However, in very high torque loads, especially in cold
> weather, where the rubber can hold more energy than normal, the some
> sort of increase in the force trying to collapse the stick seems to be
> happening. In speaking with Fred Tellier, who had noticed the same
> effect, I came to the conclusion that because the dummy part of the
> motor is neutral, and the increase motor section of a full motor is
> pulling on the stick, there should be an increase in the total
> compression load of a full motor when compared to a partial motor.
> Maybe if a few more people see this happening we could give the affect
> a name, and an equation to model the effect it has as the motor is
> scaled up?
> Nick Ray
Received on Fri Dec 01 2006 - 20:21:12 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:44 CET