b. Figure 1 shown an elevator employs a platform to move objects up and down. The objective is that when the UP button is pushed, the platform camies something to the up position. When the DOWN button is pushed, the platform carries something to the down position. The following hardware specifications define the equipment used in the elevator. Output elementa MI -Motor to drive the platform up M2 Motor to drive the platform down Input elements LS1 NC limit switch to indicate UP position LS2-NC limit switch to indicate DOWN position • START=NO push button for START ⚫ STOP=NC push button for STOP ⚫ UP NO push button for UP command ⚫ DOWN-NO push button for DOWN command Hint: NC denotes "Normally Closed" and NO denoted "Normally Open The following narrative description indicates the required sequence of events for the elevator system:- 1. When the START button is pushed, the system is turn ON, ready further instruction either going UP or DOWN. 2. When the STOP button is pushed, the platform is halted at whatever position it occupies at the time. 3. When the UP button is pushed, the platform, if it is not in downward motion, is driven to the up position. 4. When the DOWN button is pushed, the platform, if it is not in upward motion, is driven to the down position. Prepare a ladder diagram to implement the control function based on the information given above. [15 marks] Figure 1 JOE OE 10101