I'm researching human input devices to these machine and their mapping to Zmacs and Emacs. Circulating to Emacs list as well.
Does anyone have insight into the Zmacs keybindings for the Symbolics Space Cadet and/or Knight SAIL keyboards? Also any historical input on early Emacs keybindings?
I am suspicious of where the Emacs mapping of Meta and Control initially appeared. For instance on the Knight SAIL (see link below), Meta is much too far for either hand to rotate to without lifting off the keyboard. I have been told that the CTRL key on this keyboard is optimally place so the hand rotates 30 degrees, exposing a row of diagonal keys which the other hand can access. Also, the RUB OUT key is more optimally placed and much easier than performing M-x delete on modern Emacs. I am also suspicious that the Emacs Meta key is really the ALT key above rubout on the Knight keyboard. This would make the Knight keyboard much more efficient in Emacs.
I'm less certain for the Symbolics Space Cadet which seems less ergonomic and less minimalistic.
Appreciated any guidance folks may have. Also any pointers to patents that include these machines, software or keyboards. I'm not even sure what companies or grantees to search under.