Hybridization spring! Bicycle Mechanical Assistance

[raymon]

In general, is the energy recovery from braking on a bicycle interesting? In normal use of a bike on the flat one brakes little, on the other hand for a car on urban route there are many braking accelerations. The bike I showed at the start was more to show the principle.

[dirk pitt]

energy recovery by bike is only interesting in one very specific case: people who hike long distances (cyclo tourism style) because the routes are long and, if necessary, long climbs and therefore long descents and heavy bikes (luggage)
in this case, the increase in autonomy thanks to the regeneration is not negligible and the fingers and brakes are less tired during long descents of passes.
city ​​braking is negligible in terms of the amount of energy.

[raymon]

city ​​braking is negligible in terms of the amount of energy.

Absolutely, but for a car the energy recoverable in the city is much higher ex entering and leaving a roundabout.

[Macro]

city ​​braking is negligible in terms of the amount of energy.

Absolutely, but for a car the energy recoverable in the city is much higher ex entering and leaving a roundabout.

It's peanut ... When you drive eco you hardly ever brake, you anticipate and you pass everything in a rolled up ... Unless a c .. has not put its flashing and forces you to stop at the entrance ...

[Christophe]

Uh personal, I still brake more often in a car than on a bike ...

[dirk pitt]

Absolutely, but for a car the energy recoverable in the city is much higher ex entering and leaving a roundabout.

there is little difference because the energy recovered by braking a car will certainly be greater in absolute value than that of a bicycle braking under the same conditions but as it also takes more energy to accelerate the car than to accelerate a bike, the ratio is not better.

[chatelot16]

the problem is exactly the same by bike or by car ... the energy recoverable by bike is lower, but the energy to restart the bike at the next start is also lower

the question is the relationship between the energy to brake / revive and the energy to drive at constant speed

with a good well aerodynamic car we consume less time to advance at constant speed than to restart after stopping, with a bicycle or an aerodinamically bad scooter we consume relatively more to advance at constant speed, and the question of the revival braking is less important than for a car

[raymon]

with a good well aerodynamic car we consume less time to advance at constant speed than to restart after stopping, with a bicycle or an aerodinamically bad scooter we consume relatively more to advance at constant speed, and the question of the revival braking is less important than for a car

This is why it would be interesting to know the size and the weight of a spring to relaunch with 10 kw on 200 m for example.

[izentrop]

Hello,

This system with spring reminds me of the little children's cars that rub on the ground to tighten the internal spring and let go: the car starts suddenly at full speed but stops 1 or 2 m further!

Friction cars? A flywheel but no spring. On a normal scale, they would make a huge weight.

Raymon, 10 kw in a spring don't even think about it

springs are actually poor energy accumulators when compared to other devices. Thus, the accumulator battery of an automobile stores approximately 1 times more energy than a spring of the same mass would do.

https://fr.wikibooks.org/wiki/Les_ressorts/Aspects_%C3%A9nerg%C3%A9tiques

You would have to pull a trailer just to carry the spring and no question of climbing a hill.

[raymon]

Raymon, 10 kw in a spring don't even think about it

I said a power of 10 kw on 200 m not 10 kwh that has nothing to do.
10 kw for 15 seconds is 10wh / 000x3600 = 15 wh
Is the calculation correct? For 41 wh there is no need for a trailer!
I insist not to confuse kw and kwh.