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Industrial Automation, Communication and Data Management Prof. Cesana, Rocco, Tanca February 17, 2020 name: university ID number: signature: Warnings • This file consists of 10 pages (including cover). • During the exam you are not allowed to exit the room for any other reason than handing your work or withdrawing from the exam. • You are not allowed to withdraw from the exam during the first 30 minutes. • During the exam you are not allowed to consult books or any kind of notes. • You are not allowed to use calculators with graphic display. • Solutions and answers can be given either in English or in Italian . • Solutions and answers must be given exclusively in the reserved space . Only in the case of corrections, or if the space is not sufficient, use the back of the front cover. • The clarity and the order of the answers will be considered in the evaluation. • At the end of the test you have to hand this file only . Every other sheet you may hand will not be taken into consideration. Consider the automatic cart depicted in the picture: In the initial state, the cart is to the left of the rail and the valve is closed. When the operator presses a button, the valve is open until the cart is full, then the cart has to move to the right until it reaches the end of the rail. At this point the cart is rotated for 10 seconds to unload it, after which it returns to the left of the rail. Two end of rail signals ( ER and EL), one signal that informs that the cart is full CF, and one signal corresponding to the button pressed ( S) are available. Two commands for moving the cart to the right (MR) and to the left ( ML), one for turning the cart ( TURN) and one for opening the valve ( OV) are available. 1. Sketch a Sequential Functional Chart (SFC) that might be used to program a PLC…