Let the Apple Car rumors roll on. Apple has been granted a patent (number 10,384,672) for a “vehicle stability control system.”
Stability refers to the ability of a vehicle to maintain its intended course. Electronic stability control systems are intended to detect and reduce loss of directional stability. Conventional electronic stability control systems determine a steering direction by measuring the steering wheel angle, and estimate the vehicle’s intended course based on the vehicle states, such as, lateral acceleration, yaw, and road wheel speeds.
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The electronic stability control system may determine that the vehicle has lost stability based on a deviation of the vehicle’s actual measured states, such as yaw rate direction from the estimated intended course. Upon determining that the vehicle has lost stability, the electronic stability control system can apply braking at the road wheels individually and/or request propulsion torque to regain stability. For example, braking may be applied to the outer front wheel to counter oversteer or braking may be applied to the inner rear wheel to counter understeer. Apple thinks it has a better overall system.
Here’s the summary of the patent: “A control system for a vehicle includes an internal vehicle reference model that determines reference states for the vehicle that represent an expected vehicle response, sensors that determine measured states for the vehicle, and a vehicle motion control system that determines desired states for the vehicle.
“A stability determining module identifies a reference deviation between the reference states and the measured states, identifies a desired deviation between the desired states and measured states, and outputs a command for reducing the reference deviation and the desired deviation. Actuators are operable to reduce the reference deviation and the desired deviation in response to the command.”
Of course, Apple files for — and is granted — lots of patents by the U.S. Patent & Trademark Office. Many are for inventions that never see the light of day. However, you never can tell which ones will materialize in a real product.