Advanced Parking Guidance System

Intelligent Parking Assist System (IPAS), also known as the Advanced Parking Guidance System (APGS) for Lexus models in the United States, is the first production automatic parking system developed by Toyota Motor Corporation in 1999 initially for the Japanese market hybrid Prius models and Lexus models. The technology assists drivers in parking their vehicle. On vehicles equipped with the IPAS, via an in-dash screen and button controls, the car can steer itself into a parking space with little input from the user. The first version of the system was deployed on the Prius Hybrid sold in Japan in 2003. In 2006, an upgraded version debuted for the first time outside Japan on the Lexus LS luxury sedan, which featured the automatic parking technology among other brand new inventions from Toyota. In 2009, the system appeared on the third generation Prius sold in the U.S. In Asia and Europe, the parking technology is marketed as the Intelligent Park Assist System for both Lexus and Toyota models, while in the U.S. the Advanced Parking Guidance System name is only used for the Lexus system.

The initial version of the Intelligent Parking Assist System, launched in 2003, was designed for reverse parallel parking. Driver intervention was not required, as the system estimated the size of the parking space and maneuvered the vehicle appropriately. This was done by an onboard computer which used a camera built into the forward and rear of the car. Sensors located at similar locations detected the proximity of nearby vehicles. The dashboard displayed an image of the lot, and the driver would then have to determine the exact position that the vehicle in the lot via the arrows which appeared on the screen. Using the arrows, the user would set the location of the vehicle in the space. When satisfied, the user pressed the "Set" button, which then activated the IPAS. The system then took over steering control to maneuver the vehicle.

Early versions of this system had difficulty detecting objects, including cats, baby prams and pedestrians. Secondly when the driver activated the system in a too small a space, the system constantly flashed warning signals to inform the user of the danger of hitting the vehicle. User assistance is required in such situations. In 2005, an upgraded version added recognition capability for parking stripes. A later version of this parking technology, launched in 2006, added integration with parking sensors. This latest version could calculate the steering maneuvers needed for parallel or reverse parking, and help determine that the car has enough clearance for a particular space with colored screen displays which indicated adequate or inadequate space.

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Wikipedia