An idea for stored power -

[Licramite]

Ok this is just an idea, I was considering ways of storing power in a bicycle to provide a boost when you need it - without using an engine.

one way I thought was using momentum.
I have seen how if you put a weight on the outside of a wheel you can make the wheel spin longer as the momentum in the weight carries on after the power has stopped.

now imagine a tube on your wheel , in it is a stop and a weight , as the wheel spins the stop carries the weight around inside the tube, and so the weight is carried at the speed of the wheel, now if the wheel slows down , the weight carries on around the the tube till it hits the stop and then the force of the weight drivers the wheel on.

so thats the theory , whats the maths , well I,ve got 1lb weight at 15mph produces 24.5joules
so if you have it both wheels thats nearly 50 joules of energy driving the wheels round.

I admit I have a fairly shaky grasp of physics (as anyone who knows me will agree) but it seams to work in theory. - I think.

 

[Rob3rt]

If you got rid of the 1lb weight and the weight of the tube, you wouldn't need this absurd contraption to turn the wheel, you would be able to do it just as intended, i.e. with your legs since the bike would be ~kg worth of rotational mass better off!

 

[Matthew_T]

I didnt know the weight thing worked. Can understand it though.
What do you use for weight (without the tube) and where do you put it exactly?

 

[Rob3rt]

Also, if the the weight is at one point, the wheel will no longer be anywhere close to balanced. Additionally, unless the wheel suddenly decelerates the weight will be unlikely to move forward. Further, think about the braking implications, added momentum to keep you going, is added momentum you need to stop. Again, inertia will be increased having detrimental effects on accelerating.

In short, it is a ridiculous idea, like all of your others.

 

[swansonj]

so thats the theory , whats the maths , well I,ve got 1lb weight at 15mph produces 24.5joules
so if you have it both wheels thats nearly 50 joules of energy driving the wheels round.

I admit I have a fairly shaky grasp of physics (as anyone who knows me will agree) but it seams to work in theory. - I think.

50 Joules? So, a one time only energy input equivalent to roughly one second of pedalling by a pootling cyclist or one-tenth of a second of pedalling by a racing cyclist?

 

[classic33]

I didnt know the weight thing worked. Can understand it though.
What do you use for weight (without the tube) and where do you put it exactly?

Never ask that question on here!

 

[Licramite]

Thats the idea, once the weight is spinning with the wheel as the wheel slows down the weight will carry on and drive the wheel on. (the weight is free within its tube)
I accept the baking implications as were can you get a decent cake on a cycle ride.
yes it would effect the brakes , but you can get pritty powerful brakes these days.
The increase in inertia would only be initial, the internal stop would carry the weight around until it span round thetube to hit the stop the othe side.
I,m sure its been done but I can't find the application it was put to. -

its funny how many a ridiculous idea is flying around the world right now.
on the other hand you might be right -

 

[Licramite]

50 Joules? So, a one time only energy input equivalent to roughly one second of pedalling by a pootling cyclist or one-tenth of a second of pedalling by a racing cyclist?

Thats based on 15mph , obviuosly the faster you go the more power it produces, it would be fairly continous as long as it was travelling faster than your wheel. - but yes it may be to small to be effective.

 

[Matthew_T]

Also, if the the weight is at one point, the wheel will no longer be anywhere close to balanced. Additionally, unless the wheel suddenly decelerates the weight will be unlikely to move forward. Further, think about the baking implications, added momentum to keep you going, is added momentum you need to stop. Again, inertia will be increased having detrimental effects on accelerating.

In short, it is a ridiculous idea, like all of your others.

Whats cooking?

 

[Archie_tect]

Stop, just... stop.

 

[Rob3rt]

The idea is ludicrous.

As the wheel slows down, the weight will also slow down, unless it slows down at a much slower rate than the wheel it will not hit the end stop. It won't hit the end stop unless you have a sudden deceleration of the wheel such as when braking where the wheel is being slowed but the weight is still free, this is exactly the point you don't want the additional momentum. The increase in inertial will not just be initial. It will be felt every time you try to accelerate or decellerate the wheel or change your direction of motion.

 

[Joey Shabadoo]

There's no such thing as a free lunch. The only energy released by momentum is that which you've put in. You'll have to work harder to get it up to speed.

 

[Licramite]

I accept theres no free energy , it will be initially slower or require more power to start - but initially you will have an increased load on the wheels of 0.5kg on each wheel. accepting the weigt has a greater mass than the wheel so it slows less quickly than the wheel. at 15mph your .5kg weight is travelling at 6.7m/s and has a momemtum of 3.35kg.
so if your wheel slows down (you pedal slower or start to climb a hill) that 3.35kg will act upon your wheel as it will try and carry on travelling at 6.7m/s.
I accept it will act more severely the your quicker the wheel becomes slower - so it will effect your braking , (and maybe hub brakes would be better than rim brakes for this)
I don't know how long the momemtum effect would last before the weight is travelling at the same speed as the wheel.
but as stored energy it appears to have benifits
of course this could be complete hogwash and the effect is minimal , its just an idea, but I'm sure its ben applied to other things. - I,m looking at inertia engines which appl the same principle

 

[ohnovino]

If you want to store momentum, how about a flywheel:

 

[Cyclopathic]

I store up energy to use on my bike in the form of blubber.