Too cool! DIY bicycle with mechanical (flywheel) regenerative braking, assist (video)

[MetroMPG]

I haven't even finished watching the 3 minute video and am posting it for its sheer awesomeness:

Maxwell von Stein, a 22-year-old graduate of The Cooper Union, built bicycle that uses a flywheel to store energy. Instead of braking, Max can transfer energy from the wheel to the flywheel, which spins between the crossbars. The flywheel stores the kinetic energy until Max wants a boost, then he can transfer the energy back to the wheel using a shifter on the handlebars.

http://www.youtube.com/watch?v=shPgLBlBABc

[MetroMPG]

More:

http://www.youtube.com/watch?v=BOnjtEKArXk

[Old Mechanic]

Basically what I was trying to Patent for cars starting in 2004, except the engine was capable of destroking itself and becoming a flywheel for energy storage and constant speed pulse and glide, using a CVT.

Another neat thing is the bike will stand up by itself if the flywheel is spinning fast enough. Just sit there with your feet on the pedals and wait for the light to change.

regards
Mech

[Old Mechanic]

Lets take it to another level.

Aero the bike so it coasts further.

While it is coasting keep pedalling just to spin up the flywheel.

Continue pedalling then add the stored energy in the flywheel.

This allows a burst of energy for acceleration to a speed higher than you could reach through pedalling alone.

Now you have the inverse of pulse and glide using stored energy to reach a higher average speed than you could on pedalling alone.

regards
mech

[MetroMPG]

Originally Posted by Old Mechanic

Another neat thing is the bike will stand up by itself if the flywheel is spinning fast enough. Just sit there with your feet on the pedals and wait for the light to change.

That thought crossed my mind too. As did: might be hard to turn corners if that baby is spinning really fast!

[Old Mechanic]

That thought also crossed my mind when I was trying to configure a vehicle with a large spinning flywheel with a mass of hundreds of pounds. In my mind the solution was to place the flywheel with it's axes vertical to the direction of travel of the vehicle.

The issue then becomes, how do you extract the energy from the flywheel without creating a yaw effect in the vehicle itself. I remembered my 37 Ford had to rods that ran lengthwise from the engine to points on the frame several feet back. This would tend to counteract the tendency for the vehicle to encounter yaw on acceleration.
I think that might be the best solution, but I never went far enough with the vehicle to actually test that theory in a real world application.

One thing I did think of when contemplating the effect on vehicle dynamics, was that having a large vertical axes mass in a moving vehicle would contribute greatly to stabilizing any pitching motion in the vehicle. Say you went over some railroad tracks or any other similar large undulation in the road. The gyroscopic effect of the large spinning mass would go far to eliminate any pitching, or up and down movements of the mass of the vehicle itself. Basically this means the vehicle would tend to stay level instead of the front and rear pitching up and down in relation to each other.

regards
Mech

[brucey]

Gah, I need access to a CNC mill and a lathe.

[Ken Fry]

Cool. Very nice project.

Of course, the Flybrid system already works well, as demo'ed in Formula One. There are probably no fundamental principals that will change to diminish the high cost -- to get the speeds required for adequate energy storage, you end up with exotic stuff or a lot of weight.

[Piwoslaw]

Back in the late '90's I read in Mountain Bike Action magazine about a guy who welded a bike frame out of large diameter tubes and put an air pump/motor in one of the hubs. When braking the air was stored at higher pressure inside the airtight frame, then used to boost acceleration. Supposedly he was a teacher/professor and the bike was project for his students (but he was the one riding it).

[Old Tele man]

Originally Posted by MetroMPG

That thought crossed my mind too. As did: might be hard to turn corners if that baby is spinning really fast!

...shades of the WWI Gnome engines! -- "snap" turn one direction but NOT the other (ha,ha).