CHI 2019, May 4–9, 2019, Glasgow, Scotland UKThe article of record as published may be found at https://doi.org/10.1145/3290605.3300867Advances in automotive sensing systems and speech interfaces provide new opportunities for smarter driving assistants or infotainment systems. For both safety and consumer satisfaction reasons, any new system which interacts with drivers must do so at appropriate times. We asked 63 drivers, ”Is now a good time?” to receive non-driving information during a 50-minute drive. We analyzed 2,734 responses and synchronized automotive and video data, and show that while the chances of choosing a good time can be determined with better success using easily accessible automotive data, certain nuances in the problem require a richer understanding of the driver and environment states in order to achieve higher performance. We illustrate several of these nuances with quantitative and qualitative analyses to contribute to the understanding of how to design a system that might simultaneously minimize the risk of interacting at a bad time while maximizing the window of allowable interruption.The Toyota Research Institute (TRI) provided funds to assist with this researc
