After a century of loyal services the gearbox will go the way of the typewriter and the film photyography. Its replacement is ready. It is the Torque Box.
This is a combination of a differential and a speed variator. The differential amplify indefinitely the speed range of the speed variator.
The main advantages are:
- The motor can be kept running at its optimum speed and save energy.
- Possibility to downsize the motors.
- Continuous speed variation from zero speed to maximum speed.
- Very high torque at low speed. Any vehicle could climb any slope. A bulldozer could move a mountain.
- Simple construction.
- No need to develop a new technology. Differentials and speed variators have been with us for a long time.
See animation of a Torque Box at: http://www.TorqueUnlimited.Biz

 

A clever way of making a reversing CVT drive, but it hardly makes the gear box "obsolete". It still is a gearbox, more or less.