Ker-Train Research Inc.

  Variator Transmission

  Incrementally Variable Transmission

  Coplanar Gear Loops

  Bidirectional Clutch

  Sales Information



Ker-train's "Incrementally-Variable Speed Change Gearbox" incorporates a plurality of binary gear-trains with fixed ratios in the sequence X1, X2, X4, X8, etc., so that when activated on or off independently with binary control system logic, all combinations of products of the ratios of the binary gear-trains will result in driveline ratios in the order of the geometric progression X0, X1, X2, X3, X4, X5, X6, X7, etc., to XN. This provides a total of sixteen ratios with four binary gear- trains, thirty-two ratios with five binary gear-trains, sixty-four ratios with six binary gear-trains, etc., doubling the number of ratios with each additional gear-train.

The "Gemini Drive" is a drive by wire digital electronic tracked vehicle transmission with 32 uniformly spaced forward and reverse speed ratios. Kinematically identical gearboxes operate in unison to provide not only 32 vehicle speed ratios, but also 32 steering ratios. With no torque converter or hydrostatic pump/motor set, parasitic losses are low, efficiency is high (90%) and heat rejection requirements are far less than present track laying transmissions of equivalent capacity.

Attractive Features of the Gemini Family:

Ø  32 ratio forward and reverse speed main gearbox

Ø  20:1 Overall reduction

Ø  Quasi-infinitely variable (i.e., 32 steps of approximately 10%)

Ø  Microprocessor controlled

Ø  Fully automatic programmable shifting

Ø  No torque converter needed

Ø  Performance optimization—software selectable

Ø  32-radii steering gearbox

Ø  Full pivot and axis steering

Ø  Cruise control option—software controlled

Ø  Easily adapted for unmanned operation

Ø  Smaller cooling system

Ø  Unlimited towing ability (no final drive disconnection needed and no overheating during long distance towing or at high speeds)

Ø  More power for acceleration

Ø  Higher maneuvering speeds

Ø  90% efficiency 

Ø  No hydrostatic pump and motor steering mechanism (more power available)

Ø  Incorporated technology applicable to all ground propulsion needs both commercial and military.

Ø  Improved fuel economy allows long range missions

Ø  Low profile - save engine compartment space

Ø  Available engine power to the tracks during either straight tracking or during track maneuvering is through gears since a GEMINI has neither a main driveline torque converter nor a hydrostatic pump and motor steering mechanism with the results that there are less parasite and translational losses in the transmission and much less wasted engine power to cool the engine compartment for an equivalent amount of work being achieved by the vehicle.

Ø  Vehicle braking is improved by using an active power continuum between the sprockets and engine at all times, computer controlled down shifting of the transmission is activated by pressure transducers on the brake pedal to achieve an effective engine braking system in concert with a wet disc braking clutch within the transmission.

Ø  A GEMINI equipped tracked vehicle drives like a wheeled vehicle, except that unlike all simple differential equipped wheeled vehicles, front wheel ploughing does not take place. The reason being that the 32 kinematic radiuses of curvature maneuvering spectrums eliminate track skewing as caused by varying loads on the two tracks. Hydrostatic steering technology cannot compensate for this variance.

Ø  A reliable regenerative all gear system with simple computer controls is a significant advantage over the existing systems with numerous feedback circuits.

The 400 HP binary Logic Automatic Transmission is ideal for new designs and repowering of military vehicles such as M113,BMP I and BMP II. 

Current Developments:

8-Speed Fan Drive

8-Speed Automotive Transmission

16-Speed Light Truck Transmission

32-Speed Truck Transmission