Development of Semi - Automatic Electric Bike for Ban Thasala Community Thamai Chanthaburi

Abstract

This research aimed to develop the semi automatic electrical bicycle for the new way travelling of Baan Tha Sara community in Tamai, Chanthaburi province

          The vintage bicycle, in this research, is 24 inches in diameter. The bicycle used for development have a reduction gear system 6 speed levels for helping labor saving while riding and braking system for safety. For the mechanical transmission, the brushless motor with 36 voltages battery was employed. Three sequence batteries size 12 V 7 A were used in the electricity system for the energy source. The practical test of the utilization was divided into 3 speed levels consist of 15-20 km/h, 20-25 km/h and 25-30 km/h before connecting to the charging system while riding. By using those speed levels, the bicycle could make long distances as 25, 17.24 and 12.61 km, respectively per one time charging. The utilization rates of electricity were 3-4 A, 5-6 A and 8-10 A, respectively. Time to ride the bicycle using those speed levels were 1.25 h, 54.27 and 37.16 min. The practical test of the utilization after connecting to the charging system while riding was also divided into 3 speed levels same as the previous test. The electricity voltage while riding was 38-39 V in every speed level. The electric current while riding were 3.5 A, 4.0 A and 4.5 A, respectively. The suitable speed of bicycle while riding and to be comfortable for user was 15-20 km/h. Total weight of the bicycle was 31.5 kg for highest weight of user, 80 kg. The highest slope way that the bicycle could ride to was 35° by using electricity voltage 220 V 50 Hz and charging time around 3-4 h. Charging cost around 2 baht per one time charging. For the engineering economy, developing investment was around 18,670 baht. By using this bicycle, the travelling cost will be safe for 16,200 baht per year (50 kilometers) when comparing with a motorcycle. A payback period is 1.15 year, The life of the bicycle is 7 years and the depreciation is around 2,524 baht per year.