The World Solar Challenge has recently previewed the 2021 regulations. This has included a standard mannequin (“PVC Pat”), which must be able to fit into all car cockpits. The idea here is that a less cramped cockpit will reduce driver fatigue (at least to some extent).
For comparison, here are some body measurements from the standard 1988 ANSUR dataset of anthropometric measurements on 1,774 male and 2,208 female U.S. Army personnel (but scaled to a 50% male, 50% female population). Click the images to zoom. It can be seen that the new cockpits will be able to comfortably hold most people, with the exception of long-legged men, or men that are more broad-shouldered than average. “PVC Pat” also has a fairly small head.
Edit: PVC Pat is clarified in this BWSC bulletin.