Torque sensor based electrically assisted hybrid tricycle: from design to development

Abstract

The tricycle, commonly known as rickshaw, is a human hauler. It is the most popular form of transport in several developing countries of South Asia, mainly due to its convenient door-to-door service. The task of pulling rickshaws is so exhaustive that almost 40% of the pullers suffer from severe health issues [1]. Nowadays, the availability of electric rickshaws has alleviated such problems. These rickshaws are merely throttle controlled which do not incorporate puller's assistance, hence putting excessive pressure on the motor. A torque sensor has been introduced to ameliorate this system. The paper starts with characterizing the electrical aspects of the throttle controlled rickshaws. Gradually, it introduces the torque sensor to those rickshaws making them power assisted vehicles. This involves an intelligent controller that combines human effort from the puller with the power of a brushless DC motor, hence giving rise to a hybrid vehicle. Finally, the results obtained from field tests show that the hybrid system requires about 32.38% less power as compared to that of the throttle controlled system which is quite significant. The hybrid system assists the puller only when needed, thus saving the motor from being overused.