Any automotive powertrain system involves the need for motive power from the engine to be converted into forward (or reverse) movement.

With a conventional powertrain this is achieved with the aid of a gearbox and a clutch to apply varying combinations of torque, as well as speed, according to driving conditions and driver preferences.

Gearboxes are mechanical devices that deliver their power output according to fixed ratios that reflect the characteristics of the individual cogs engaged at any given moment.

Variable Transmission Technology

From an engineering point of view a variable transmission device is, conceptually, preferable to a conventional gearbox with its fixed gear ratios. This is because variable transmission allows varying combinations of speed and torque to suit conditions and driver/operator preferences.

Infinitely variable transmissions take this approach to its logical conclusion. dDrive is an infinitely variable transmission.

The benefits that variable transmission (and in particular an infinitely variable transmission like d-Drive) can be expected to deliver include the following:

• Improved vehicle performance for any given quantity of fuel;
• Improved environmental performance through reduced emissions;
• Improved torque in the critical low-end revolutions range;
• Reduction in moving mechanical parts;
• Lower wear and maintenance; and
• Enhanced driving experience.

The dDrive Difference

Variable transmission devices currently available are essentially belt-driven or toroidal systems that transmit motive power by applying pressure directly to smooth, non-geared, surfaces. They are based on processes originally patented in the late nineteenth century with subsequent improvements based on materials used and methods of construction. Belt slippage and heat loss are common engineering problems with these designs which struggle to deliver torque – especially at low revolutions when it is often most needed.

dDrive, in contrast, represents a complete new concept in transmission design. The key difference is that gearing ratios are altered by purely mechanical means with power being applied directly to individual gears according to conditions and driver/operator preferences. The use of gears (with teeth) makes dDrive much more efficient in mechanical terms than other systems and substantially mitigates the problems of low torque and heat loss. Infinitely variable transmission is achieved through the arrangement of the gears.

dDrive does not require a clutch. The engine can be started in powered neutral position, and gear ratios can be changed up and down, through the entire range, and even into reverse, all in one smooth motion and without disengaging the gears.

Commercial Applications

Potential commercial applications for dDrive are certainly not limited to its obvious use in automotive powertrain systems. dDrive in fact has potential for deployment in virtually any situation that requires variable speed – or even where a variable power input needs to be converted into a constant output speed.

Possible markets (all of them requiring variable speed transmission and all of them essentially global in nature) with significant commercial potential for dDrive include:

• Automotive – including, more specifically, cars, heavy and specialist vehicles (eg. mining and airport towing vehicles) and motorcycles as specific market segments and including the emerging electric vehicle market;
• Electric/hybrid vehicles specifically as a discrete segment of the overall automotive market where dDrive could be applied to a regenerative braking/battery charging function;
• Marine;
• Rail;
• Aerospace and Defence;
• Industrial conveyors;
• Outdoor power equipment;
• Clean technology infrastructure such as wind turbines; and
• Robotics.

Engineering Support

Our commercialisation strategy involves seeking potential engineering partners and opening discussion with them at an early stage both to assess their possible interest and contribution and to identify other possible commercial applications for dDrive.

dDrive has been the subject of independent mechanical testing by specialist test engineering company, e3k (a part of Gilmore Engineers Pty Ltd) which has confirmed the commercial potential of the product. You’re welcome to view the dDrive Transmission Report.

We have also received correspondence from Ferra Engineering (though they have not at this stage made any formal assessment or carried out any testing) confirming their view of dDrive’s commercial potential.