The importance of including knowledge of neuromuscular behaviour in haptic shared control

Haptic shared control is a powerful way of combining the best of humans and intelligent vehicles, keeping humans in the loop while avoiding many automation issues. Literature has shown that haptic shared control can support drivers to increase performance at reduced control effort, but also points out that even then, subtle conflicts occur between driver and shared controller. This paper hypothesizes that at least part of that disagreement lies at the neuromuscular level, and that mismatches in expected torques will result in decreased performance and increased effort. The goal of this paper is to provide experimental evidence that shows the importance of tuning guidance torques with the correct expectations about neuromuscular response. An abstract steering experiment was performed without visual cues, where drivers were guided by haptic shared control torques to perform a lane-change maneuver. The torques were tuned with three different expectations about driver's neuromuscular behavior, and drivers were also instructed to perform three different neuromuscular tasks. The results show that when the tuning of the torques did not match the real neuromuscular behavior, guidance torques were either too high or too low, and performance was reduced. It is concluded that a good understanding of neuromuscular response of drivers is essential to avoid subtle conflicts between driver and shared controller.