Nowadays there are few standard plugs for e-vehicle charging. They cannot be used for robotic charging due to the need for precise pushing. My idea is to produce a simple socket in an e-vehicle (picture 1 top) and plug (robot hand).

Socket construction is very simple. Plug (robot hand) consists of two group of contacts. First, group metal balls (a,b,c,d). Second, metal rod in a center of plug.

How it works. (picture 2)
Phase 1 pushing.
Phase 2 adjusting until all contacts (a,b,c,d) become electricaly connected together through metal ring in a socket.
Phase 3 rod pushing.
Electrical gear pushes rod until it fully goes into socket.
Metal balls goes into socket ring trench.

Key benefits
Simple, safe, auto adjustable, suitable for big electric current and high voltage.

Can be used as robot's hand.

There is the possibility to detect position and control adjustment using an electrical circuit.