VEX Three Stage Elevator

A Three-stage elevator created using VEX parts that can go between floors in any combination. Custom build and code. This Instructable records my design/iteration process and is not necessarily step by step ;)

1. Structural:
2. VEX metal base plate
3. C-channel metal beams
4. L-brackets
5. Flat metal plates
6. Standoffs and spacers
7. Metal gussets for reinforcement
8. Motion (Geartrain)
9. Gears + chain
10. Steel shafts
11. Shaft collars
12. Bearings
13. Electronics
14. VEX Cortex
15. Motor controllers
16. VEX motors (393)
17. Battery holder
18. Wires and extension cables
19. Software
20. RobotC for VEX Robotics

Created several ideas and decided what to pursue through a decision matrix based on hardware simplicity, software simplicity, and build time. (Final sketch and isometric drawing shown)

Created several code structure ideas and decided what to pursue through a decision matrix based on complexity, time to write, and types of loops utilized.

1. Started building the structure for the elevator floor mount
2. Built the elevator box and attached it to the belt that will move between floors with a rubber band, tensioned by several screws
3. Sized the belt to fit with our gears and assembled it to the base

1. Resized the Chain to fit/tension better around the gears
2. Set up motors and sensors:
3. So far we have:
4. 1 model 393 motor
5. 3 LED lights (1 for each floor)
6. 1 ultrasonic sensor
7. 6 bump switches
8. Final adjustments to the Chain to fit better around the gears
9. Mounted chain and elevator box vertically
10. Mounted motors and sensors onto the base

1. Code structure ended up not deviating at all from the pseudocode structure (besides tuning that needs to be done with our variables)

1. Re-mounted bump and limit switches
2. Tested motor:
3. Adjusted speed
4. Added counterweight
5. Added another support bar for the gear shafts so they don't tilt from the weight of the chain
6. Added a limit switch to the top level, and it works 100% of the time now
7. Final tuning in code for defined heights and speed.
8. Build is done!

What my elevator build does:

1. Three levels with a limit switch on each level, as well as on the test bed that calls the elevator to that floor
2. LED lights displaying which floor the elevator is called to
3. When the elevator is not being called, it goes to a default position of the ground floor
4. The elevator can go to all 3 floors in any combination