CapaciCar - Tomorrow's Technology Today
BLOG 9 - Steering...
...To Avoid Veering
25-02-16
With the rest of the car nearly there we decided to get on with the steering. It was decided early on that incorporating some sort of steering system would be helpful as this is more real life than just having a fixed axle. A variation of the rack and pinion method was chosen as the optimum method as it was simple but still effective solution. With the decision to use two motors of the rear axle this meant there was no need for a servo motor and a gear and just by changing the speed of the rear motors the car will turn. This lead to a final decision as shown.
The only thing left to decide was the length of the steering arms. The length of the steering arms directly affects the ackermann angle. The ackermann angle is used as both the inside and outside wheels turn at a different angle to go round a corner. Therefore you need the perfect Ackermann angle to make sure neither wheel scrubs. The perfect Ackermann occurs when you draw a straight line between the king pin and the steering arm pivot and it intersects the centre of the rear axle. The king pin is the point of rotation connected to the axle.
Now the car has the perfect Ackermann angle it can turn beautifully as can be seen on our video on the home page of our website.
Ackerman Angle
"Now the car has the perfect Ackermann angle it can turn beautifully"