Similar in size to a gokart, Roadbot 3 and Roadbot 4 have streamlined bodies, minimal frontal area and low rolling resistance tyres. They are powered by brushless DC electric motors and a lithium battery packs.
They were built to compete in the Perth EV Challenge in Western Australia by the River Raiders team.
Step 1: Planning and Models
This year we are using 20” wheels and are building 3 and 4 wheel cars. The 20” rear wheel, down from 26” in previous years allows a more reclined driving position which reduces the frontal area. The 20" wheels are also stronger for side loads than large bike wheels (note a bike does not apply side loads to a wheel when cornering) but have a slightly higher rolling resistance however at speeds over about 30km/h, reducing wind drag becomes more important than rolling resistance.