Hi Henry
I'm still getting used to this forum and I haven't been able to quote one of your comments.
I said --- "the inputs for the atmega device have hysterisis, then the sensor switches can be connected directly to the device, eliminating the 74HC14 completely, reducing the component count to a minimum."
You said -- "I don't know how the hysterisis (either on the atmega or hc14) would have eliminated the need for debouncing. Your circuit would have worked with a non-ST gate and the atmega, with hysterisis, would malfunction without a debouncing approach."
The schmitt input would of course need an RC circuit to hardware debounce. However, the RC circuit by itself would not provide a reliable debounce action without the schmitt trigger.
I must add however, that I have come to the conclusion from all the comments here, (but accepting that I do not have full access to Ironbot's design) that the best way for Ironbot to go, is to software debounce. If this is a learning exercise, it would be a valuable bit of experience anyway.
You have started an interesting string Ironbot.