Current automobiles all provide the driver with a pedal (or similar mechanism) to accelerate the vehicle by delivering acceleration to some or all wheels of the vehicle. The acceleration is generated by a series of steps which result in greater power being generated from the engine which is then delivered to the wheels. However, all current systems deliver the same amount of power to each wheel in order to keep the vehicle stable and maintain linear motion.
The present invention proposes an apparatus and method to allow the driver to control the amount of acceleration delivered to each wheel independently and thereby control the velocity of rotation of each wheel separately thereby giving the driver tremendous control over the motion of the vehicle. The present invention allows the driver to easily execute driving motions that are not possible with conventional vehicles.
Existing vehicles do not provide the driver with the capability to control the acceleration delivered to each wheel independently of the other wheels. When a driver accelerates a vehicle, all powered wheels receive the approximately the same amount of acceleration. Similarly, when the driver applies brakes, each wheel is slowed down in approximately the same proportion.
The present invention proposes an apparatus and methods that allow different amounts of acceleration or braking to be delivered to each wheel, provide the driver with an easy and intuitive interface to control the amount of acceleration or braking delivered to each wheel and methods to prevent poor inputs or sequence of inputs from the driver from destabilizing the vehicle, such as over-accelerating some wheels or braking too hard on some wheels. While the invention is here described primarily in reference to a four wheeled vehicle, it can be generalized to a vehicle with any number of wheels.
A driver facing interface is proposed that allows the driver to control the amount of acceleration delivered to each wheel as well as separately control the braking on each wheel. The interface consists of a modified acceleration and braking pedal with multiple touch points, where each touch point produces a different effect. The pedal consists of five points where the driver can apply force, each point spatially separated from every other so there is no overlap of force application from driver and designed so as to provide the driver with easy and cognitively distinct access to each point. Cognitively distinct implies a design whereby the driver knows by the mere touching of the point with his feet, which of the five points it is. The five separate points give the driver ability to control power delivery to the left front wheel, the right front wheel, left rear wheel, the right rear wheel and all wheels simultaneously in a four wheeled vehicle. So the driver can apply force to a given point on the pedal to control delivery of accelerating power to that particular wheel or all wheels in case of the all-wheels point on the pedal. Similarly, the brake pedal is implemented in the same model, and allows the driver to control delivery of braking force to each or all wheels independently based on how much force the drivers applies where on the pedal.
The differential acceleration or braking power is delivered to each wheel using a simple drive by wire system which controls the braking signal delivered to each wheel separately. However, all signals emanating from the accelerator or brake pedal are run through a Stabilizer System which uses various points of data including the current velocity, direction and requested acceleration or braking, to modulate the actual acceleration or braking delivered to the selected wheel in order to maintain vehicle stability. This Stabilizer System however, can be switched off at the choice of the driver, in which case, the acceleration or braking as chosen by the driver will be delivered directly to the wheels. The Stabilizer System processes the inputs from the acceleration and brake pedals before they are sent to the engine, transmission or the brakes, and modifies the final signal to each component if it calculates that the requested inputs would destabilize the vehicle.
Given the design of most commercial vehicles, a sophisticated apparatus is required to deliver differential acceleration to the wheels. In most conventional vehicles the power is delivered through a transmission system to the differential which in turn delivers the accelerating force to the individual wheels. Since all wheels are powered by the same transmission, they all receive the same amount of power, though the torque may be varied by the differentials. In order to differentiate the power delivered to a given wheel, from the power delivered by the transmission, a power modulator is connected between the transmission and the wheel. The power modulator translates the power from the transmission into power to the wheel, and can step it up or down as required. The power-up and power-down actions are controlled by signals from the driver based on the application of force by the driver on the multi-point acceleration pedal. When the driver chooses to increase the power delivery to a given wheel, a signal is sent to the associated power modulator to increase the power for that wheel. However, when driver wants to accelerate all wheels identically, the power modulators are disengaged and power is delivered to the wheels directly from the transmission. On the other hand, in another model, when driver requests more power to a given wheel, system engages the transmission to increase power output to all the wheels, however, the power modulators transmit the additional power only to the target wheel(s), and prevent any additional power from being to delivered from the transmission to the non-targeted wheels.
The stabilizer system reads the signals from the acceleration and braking pedals generated through the application of force by the driver to different points on the multi point pedals. The stabilizer reads the current vehicle dynamics—speeds, stability, momentum—as well as simulates the impact of the requested actions to predict the impact on vehicle stability and accordingly adjusts the actual signal delivered to the wheels in order to minimize risk and keep the vehicle stable. The actual signal output from the stabilizer might involve increasing or decreasing the requested acceleration amount, adding acceleration to other non-selected wheels, braking on some other non-selected wheels etc.
Advantages
The present invention allows the driver to carry out actions that are not possible with conventional vehicles. It gives the driver much greater cornering and turning capabilities and potentially much more powerful handling. It also allows driver finer control over the motion of the vehicle. All these advantages in turn allow the driver to execute creative maneuvers, stabilize vehicle when he loses control, safely exit from dangerous trajectories and in general achieve much greater control over the motion of the vehicle.
Alternative interfaces: The driver interface for differential acceleration and braking can be implemented in some other models as well, apart from multi-point pedals, as described below:
This application claims the benefit of priority to U.S. Provisional Application 61/838,316 filed 23 Jun. 2013, the entire disclosure of which is incorporated by reference.
Number | Date | Country | |
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61838316 | Jun 2013 | US |