The drive toward a hybrid transmission

In-wheel hydraulic motors, hydraulic transformers, and a common pressure rail with accumulators put new meaning in the word drivetrain.

Hybrid-electric vehicles are compromises. The pure mechanical transmission is unparalleled when it comes to cost, weight, and efficiency. On the other hand, gear transmissions and even CVT's lack flexibility regarding energy management, energy transformation, and energy storage. Electric systems are in this respect much more convenient, but the power density and the efficiency are too poor to make a full electric drive feasible.

However, Innas believes that if a flexible, nonmechanical transmission principle could be found with the same performance, cost, and efficiency as existing mechanical transmissions, there would be no reason for a hybrid configuration. And, the company claims that it has found it: a full hydrostatic all-wheel-drive system that eliminates the complete mechanical drivetrain between the engine and the wheels. The company refers to its hydraulic hybrid transmission as a “hybrid.”