Kristin Wall
Oct 27, 2011

Hate driving in traffic? Your car can make it better!

Everyone hates driving in traffic. The stop and go. The lurch when you accelerate for a moment, then are forced to slam on your brakes when someone cuts into your lane. It’s uncomfortable, unpleasant and fuel-inefficient, not to mention bad for the environment and your health (studies show traffic pollution can speed arterial hardening). Until now, that is. General Motors has patented an invention for a car that will give you a smoother, greener, less costly ride when you’re sitting in bumper-to-bumper traffic. Commuters of the world, rejoice!       Many hybrid vehicles already feature technology that allows the internal combustion engine (ICE) to shut off when the driver applies the brakes and stops the car to cut down on fuel consumption and emissions. When the ICE is disabled a motor generator unit (MGU) runs on battery power to operate vehicle accessories, like the radio and air conditioning. When the driver decreases brake pedal pressure, the MGU shuts down and the ICE restarts to allow the vehicle to accelerate.   GM’s latest patent, “Creep mode propulsion for stop-start hybrid vehicles,” expands on this existing technology to allow the car to accelerate while the ICE is still shut down.     The patent discloses a control module including a traffic determination module that selectively generates a traffic signal, which in turn activates a creep enable mode that generates a creep enable signal. When the creep enable signal is activated, a power control module selectively generates an internal combustion engine disable signal, while at the same time activating a motor generator unit to produce power as the driver reduces brake pedal pressure.     The control module determines the vehicle is in heavy traffic based on the number of successive starts-and-stops within a predetermined period, or alternatively, based on traffic determination modules that measure distance from other vehicles. Once creep mode has been enabled based on the vehicle’s traffic determination module, when the driver reduces brake pedal pressure, the MGU, rather than the ICE, propels the car. The control module may command the MGU to accelerate up to a predetermined speed, and may increase speed at a predetermined rate to provide smooth acceleration. The ICE remains off, which reduces emissions and increases fuel economy. If the driver presses the accelerator pedal, the MGU shuts down, disabling creep mode and restarting the ICE for normal vehicle function.