Do I still need a perimeter wire for a robotic mower?

Increasingly, no. Most of the newer picks here (Segway Navimow, Mammotion LUBA 3, both ECOVACS Goat models, ANTHBOT, and Husqvarna's EPOS/iQ line) use RTK satellite positioning, LiDAR, or camera vision instead of a buried boundary wire. Reviewers note wire-free setup is dramatically faster, though RTK-based units can struggle under heavy tree cover where the signal weakens.