The Pilot Pull: An Idea Turned Reality by Honda’s David Bartlett
Posted: October 16, 2023
When David Bartlett first got involved with SAE International as an Baja SAE participant in 2003, he never imagined that 20 years later he’d be shaping the event.
Since his student participation, the Technical Expert in Brake Performance Group, Chassis Division at Honda, has transitioned into a volunteer role at both Baja and Formula SAE as a Design Judge.
While volunteering at the 2022 Baja SAE Arizona competition as a Design Judge, Bartlett began to reimagine the sled pull event. He pondered how event organizers could take a Honda vehicle and utilize the electric assist brake system integration to slowly resist the pull of the Baja Car.
Bartlett knew that to pull it off, he needed some help. He sought the help of Andrew Knepper, Dynamic Chassis Controls Senior Brake Engineer at Honda, and together, they were able to develop this idea into reality for the 2023 competition season.
“We’ve connected to the vehicles CAN bus [Controller Area Network] between the Vehicle Motion Control ECU and our Electric Brake Booster and are monitoring the distance the vehicle is pulled using the OEM wheel speed sensors,” Barlett said. “A brake torque request is sent to the brake actuation system via an Automatic Cruise Control signal where the brake torque is increased linearly based on distance, but the rate of increase can be tuned prior to the start of the competition based on the course conditions and the level of difficulty desired.”
The challenge, put simply, is this: a Baja vehicle is tasked with towing a Honda Pilot. This is particularly difficult with a lighter vehicle, but minimizing the Baja car’s mass is important for its performance in other dynamic events.
The Pilot Pull technology Bartlett describes was first applied during the 2023 Baja SAE Ohio event. This new challenge provided another outlet for the young engineers to practically test their skills.
“This technology is beneficial for the students participating in Baja SAE because it shows how we can utilize hardware and software for multiple purposes. Approximately ten percent of the brake systems capability is utilized to stop the Baja Car. The brake pad temperature saturated at 50 C during the event so the robustness and repeatability of the results are very high which should give the students more confidence in their score,” he said.
In addition, the distance each car is able to travel is directly related to a torque requested by the brake system. So, each team will be provided with a whole vehicle torque capability, something that could be used in target setting and engineering processes for the following competition season.
Bartlett has worked around the world for Honda and is uniquely suited to bring this opportunity to the Baja competition. In 2015, he was selected for an overseas assignment to study the brake systems for hybrid and battery electric vehicles in Japan. There he learned about tuning the brake by wire system that is implemented in Honda’s vehicle lineup today.
In addition to his work at Honda, Bartlett has been heavily involved in the University of Dayton’s SAE Chapter prior to his overseas assignment for Honda holding multiple roles including Chairman of the Board.
Learn more about Baja SAE and stay tuned for the 2024 competition.