Conveyor Sort — 3D Cell

Briefing

Boxes travel along a main conveyor. An entry photo-eye announces each arriving box. A second photo-eye mounted at a known height differentiates tall boxes from short ones. Tall boxes must be diverted onto a second conveyor by firing a pneumatic solenoid while the box is passing the diverter arm; short boxes continue past undisturbed. A counter watches the divert lane's limit sensor and lights a lamp once five tall boxes have been successfully diverted.

Objectives

• START energises MAIN_MOTOR; STOP de-energises it
• Fire DIVERTER_SOL so that tall boxes are pushed onto the divert lane
• Leave DIVERTER_SOL off for short boxes
• Light TALL_COUNT_LAMP once 5 tall boxes have cleared the divert-lane limit sensor
• Never energise DIVERTER_SOL while ENTRY_PE is still broken — the arm would collide with the box

I/O Table

Your program will be tested against:

All test cases run automatically when you submit. Assertions are hidden until you pass.

1. #1Start energises main motor, stop drops it

   START -> MAIN_MOTOR on; STOP -> off

2. #2Tall box fires the diverter solenoid and is diverted

   Inject a tall box: solenoid pulses for the transit window, box reaches the divert lane

3. #3Short box passes without firing the diverter

   Inject a short box: diverter solenoid remains off throughout the run

4. #4Mixed flow counts five tall boxes and passes a short box

   Tall boxes divert while a short box continues on the main conveyor; TALL_COUNT_LAMP energises after the fifth tall box

5. #5Diverter never fires while a box still breaks the entry beam

   Inject a tall box; assert the solenoid was never energised while ENTRY_PE was active