Posts filed under: Friction Circle

Friction Circle

Driving Tips

Tire Sidewall Flex & Relaxation Periods

Relaxation Periods As a racecar goes from the different loads for a typical corner — acceleration, braking, cornering, acceleration — transition periods occur as the tire’s cords settle down into their tasks at hand.  As the tire transitions to-and-from the... Read More

Ayrton Senna Footwork

Ayrton Senna at Play in an Acura NSX Ayrton probably didn’t have a lot of seat-time in this car when this was shot. So, the amount of lock needed to dance it around the corners wasn’t as ingrained as it... Read More

Load vs Traction – How the Whole Car is Affected

Ross Bentley does a great job of simplifying how load curves work in relation to cornering force. In fact, the load curve can be mixed with the slip-angle curve to get a 3D “carpet plot” of traction force available at... Read More

F1 1978 Long Beach Grand Prix with Patrick Depailler

Jacques Villeneuve spoke about boredom in F1 in this BBC story: http://www.bbc.com/sport/0/formula1/26178312. Back in the ’90s, I worked quite closely with him in IndyCar. I found him to be one of the most talented, level-headed drivers on the circuit. He... Read More

Racing Steering Wheel Grip Design Tips

As inventor of the PersonaGrip custom-molded racecar steering wheels, I discuss designing the top wing on a racing steering wheel in this video. Lessons learned from the world’s best drivers in IndyCar, Formula One, NASCAR, ALMS, et al. over the... Read More

Slip Angle vs Attitude Angle — a Novel Approach

Dale’s explanations are simple, and his approach is beautifully unconventional. Differentiating between “attitude angle” and slip angle took a second to visualize, but his torques about the car’s CG are spot-on…bravo, sir.... Read More