Mechanical Relay Logic Elevator Controller Model

I will be presenting an all-mechanical relay logic elevator controller, the Elevatron Mark I. It includes all the same features, and more, from the original elevator control systems made in the late 1940s and onward, until computer-based control systems took over in the late 80s/early 90s. The system includes all the parts that make up a traditional architecture of a CPU, except that it will be done with mechanical relay logic only. The fundamental rule of this project is: no computers of any kind or advanced semiconductors are allowed. Along with the controller is a 10-floor model of a typical traction elevator setup so that the controller will have something to interface with. This includes all the call buttons on the floors, the arrow lights, chimes, floor buttons in the car, and more. Essentially, it will include everything that makes up a real system. The floor labels of the elevator model are based on the Sol dorm building, so floors A through 9, 10 in total. The relay logic forms parts of a CPU as we know it today, but in mechanical ways. This involves the following: Inputs - limit switches, buttons, safety devices Outputs - bells, buzzers, motors, lights, fans, analog displays Latches - instruction order regulation, hall/car call tracking, reset triggers, output indicators Logic gates - AND, OR, NOT, NOR, NAND, XOR Volatile memory - hall/car call tracking, car's direction, system state Non-volatile memory - mechanical selector units to keep track of car position and direction Capacitor-based timers - door timer, nudge mode timer, flasher units for outputs CPU architecture - whole system is broken down into separate modules that work together to form the system logic Full asynchronous control - well, there's no computer, so the system has no clock! This project primarily serves as a proof of concept demonstrating that it is possible to make a computer using just mechanical switches and relays, with little to no semiconductors. It is also great to be used as a demonstration of an application of low-level computer systems to visually see the logic in action while the system is in operation. The most exciting part of this project is that nobody has ever attempted to build this system since the last ones were made in the 1980s-1990s. So, on the internet, nobody can really explain how these relay logic control systems work, even with the schematics (which are hard to find in itself). I was able to figure out how these things work by finding some real examples around the Rochester area, learn the system's behavior, and come up with a mechanical contraption that acts as a "computer". Thus, I came up with the Elevatron Mark I controller.