The big player are Lamassu, Skyhawks,  Genesis and a few others you will find on this list of the top 6,
https://themerkle.com/top-6-bitcoin-atm-manufacturers/

Robocoin had a big share at one stage but they also had the worst user friendliness, palm prints, ID scans the works to invade your privacy so I am not surprised to not see them on the above list.