Polestar - The anatomy of performance

Performance has traditionally been measured in numbers: horsepower, acceleration, cornering G-forces and lap times. But as electric cars increasingly level the field by delivering extraordinary levels of traditional performance, a new question is emerging: how do we measure what performance feels like to the human behind the wheel?

A new pilot study by researchers from the University of Oxford’s SDG Impact Lab, in collaboration with Polestar, has taken a first step towards answering that question. The study combined vehicle telemetry with heart-rate monitoring, eye tracking, psychological assessments and interviews to explore the relationship between what a performance car does and how the human driver responds.

Twelve drivers drove two versions of Polestar 4: Rear motor and Dual motor with Performance pack – in both calm and dynamic driving conditions at Gotland Ring in Sweden.

The pilot found that several measures were sensitive to changes in driving conditions and vehicle performance. During dynamic driving, participants blinked less, their pupils became larger and they held their gaze longer – patterns consistent with deeper attentional engagement. Vehicle telemetry could also be linked to changes in drivers’ physiological activation, allowing researchers to examine the driver’s response alongside what the car was doing.

The comparison between the two cars also revealed differences in how performance was delivered. On matched fast laps, the Polestar 4 Dual motor with Performance pack made use of its considerable power increase over the Polestar 4 Rear motor (400 kW/544 hp versus 200 kW/268 hp) to deliver greater peak performance and less steering effort on circuit: 32% higher peak acceleration while requiring 15% less steering effort. It also generated greater cornering loads and more frequent hard-acceleration events.