Bicycle Gears

It is not unusual to see 30 speed gear bicycles. I know various terrains need different gears to climb and if I want to go faster I change gear. What is needed is actually a way to keep constant speed regardless of terrain.

Today's bicycles are all gear centered. When you change gear, you alter the speed and hence the power to drive it. There is a concern about cadence also. Usually, people want to keep constant cadence but once the gear changes, the cadence also changes. It takes quite a bit of experience to keep cadence speed.

Usually I keep the front gear for terrain change and the back gears for speed. Most people just arbitrarily alters it to keep a constant cadence. But I do know novices who simply have no idea which is for what.

I was thinking whether there is a way to keep cadence and speed but alter the power when climbing hills. After all, you need to apply more power if you climb hills. By changing a setting, the pedal lever arrangement changes so that the power transfer will be different. Currently, the gear set at the  pedal does that but it changes the speed also. The gear set at the wheel does exactly the same making it somewhat redundant.

If it is possible to change the lever arrangement without changing the speed then the only thing that changes is the power applied to the gear. It is then easier for the cyclist to adjust to heights by just adjusting the lever arrangement or apply more leg power.

Obviously, there is a need to change speed. Well, the gear set at the back wheel is still available. It is now even easier, If I need speed, I just change the back gear without affecting the cadence.

Whether it is technically possible is another question. This idea is more suitable than current gear set based bicycles.