A multi-purpose four-wheeled two-passenger electrically assisted human-powered vehicle (EHPV) prototype is created to be used by people with physical disabilities, such as a person who does not have full strength in his or her legs. Additionally, the EHPV can also be used as a rehabilitation device, where an instructor can aid in pedaling the vehicle. The EHPV also functions as an alternate form of transportation for the environmentally conscious consumer, and is suitable as a recreational vehicle. The vehicle functions as a recreational vehicle and an alternate form of transportation. The cargo area can be used to store medical equipment needed by the occupant or leisure equipment for the recreational user.
The electrical assistance in the EHPV is primarily for assistance in uphill climbs, or traversing rough terrain where pedaling may become difficult. The electrical assistance may also be used for aiding an individual who does not have the strength or ability to pedal during normal driving conditions. The electric motors are powered by batteries that can be charged prior to use. The user has the option of engaging or disengaging the electrical assistance depending on riding conditions and preference. To ensure a comfortable ride, the EHPV is equipped with four-wheel suspension. To prevent loss of braking in wet conditions, enclosed drum brakes are used. For safety, the EHPV is equipped with a brake light, reflectors, lights, and turn signals.
The power is transmitted from the pedals through an axle to the front wheel axle and then to the rear axle by a drive chain. This prevents the chain from dragging on the ground. The chain is enclosed for safety. The front suspension is a single A-arm design with an upper control arm. The A-arm is an independent suspension that uses curved members (wishbones) to control suspension travel. A wishbone suspension offers good axle control, limits undesirable suspension and helps to ensure good handling. The rear suspension is a swing arm design, with the outer arms of the swing arm placed outside of the main body of the chassis. The vehicle is steered by the left-side passenger using a steering wheel attached to the front axle via linkages that allow a limited range of motion. The rear axle is a powered motor and a direct chain drive. All the motor controls, housed in a console between the two passengers, turn the motor on and off and adjust the motor’s speed. The total prototype cost approximately $1900.