In order to test our torque vectoring system works and its benefits, we decided to compare the turn radius at different steering angles and compare it a front-wheel-drive drivetrain. Figure 1 below shows the results of our testing. We tested our car at various angles from 10 to 20 degrees. From our data, we plotted the graph below. The orange line represents data from FWD and the blue line represents data from torque vectoring. From the graph we can see that as the steering angle is increased, the turn radius is improved almost exponentially. The install trend of the exponential growth is a little obscure, but as the angle becomes larger the trend is more obvious. The grey line on the top corresponds to the right axis which is percentage of difference compared to FWD system. As we can see, the percentage of growth is almost linear.
Figure 1) Turn radius vs. Steering angle
We noticed, however, that torque vectoring system puts a significant large amount of force on the front axle. Our theory is supported by the centripetal force equation–F=mv^2/R^2. In the equation, we can see that as the radius gets smaller, the centripetal force is increased exponentially. Too large of a force may exceed the limits of the suspension or the grip of the tires.
From our results, it has been proven that torque vectoring system has a better performance in maneuverability and steering stability without differential mechanism in combination of braking. However, torque vectoring puts a significant more amount of forces on the tires and the steering mechanism. The system would require better performance tires and a more robust steering mechanism. The ESC (electronic stability control)system should also be carefully reprogrammed before putting into production for racing or commercial.