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feature article may 2019 GOLF CART A ROLLOVERS ccording to the Consumer Products Safety Commission (CPSC), there are approximately 15,000 golf cart related injuries requiring emergency room treatment in the US each year. Some 10% of these accidents involve a rollover. http://www.technology-assoc.com Golf carts are typically designed with brakes only on the rear axle. As our engineers have addressed in several peer-re- viewed journal papers, this can result in the vehicle becom- ing unstable. A golf cart rollover often occurs as a result of a driver losing control of the car while traveling downhill on a car path. One potential source of a downhill loss of control is the current industry practice of manufacturing golf carts with brakes on only the rear axle wheels. It has long been under- stood that a braked vehicle with skidding rear tires and rolling front tires is directionally unstable but this instability will not always manifest itself when a vehicle is traveling at sufficiently low speeds on level ground. However, besides reducing brak- ing effectiveness (when compared to four-wheel braking), rear wheel only brake designs can easily lead to “fishtailing.” Furthermore, the reduced braking effectiveness on downhill slopes can lead the driver to falsely perceive a brake failure, causing him to press harder on the brake pedal, which in turn leads to a locking of the braked wheels and an out-of-control skid. This hazard is aggravated at golf courses that incorpo- rate hilly terrain with steep, narrow golf cart paths and sharp turns. Such conditions make it desirable to create golf carts with good braking characteristics for use on courses with downhill slopes of 10 degrees or more. Industry standards for the design of golf carts contain minimal braking requirements that do not include tests for MAY 2019 5