For years, EUN has manufactured automatic shelving units. This type of shelving units increases the working surface area of a warehouse by permitting them to be moved, so that it is a simple matter of opening up an aisle to access each of them at any given time. The chosen system is based on a PLC and starters to control the DC motors. The client wanted to manufacture a customized version of the starter.
Starting with the client’s original idea, we analyzed their needs and development possibilities. The conclusion was reached that the optimal solution would be the development of a complete control system, eliminating the high cost associated with the PLC and adding new features. The old system, based on a centralized PLC, was replaced by a new, decentralized system, where each cart had its own control system. Two different boards were designed:
High-end capacitive keyboard:
Based on a 18F-series PIC. Includes an RFID reader for managing permissions for access to each shelving unit. Enables several keyboards to be installed at each shelving unit
Also based on PIC 18F. Controls the DC motor. Permits smooth start-ups and stops, as well as active braking (the motor acts like a brake). It also implements safeties to detect people who are trapped. Includes an RS485 communications interface for connection to the rest of the shelving units and another RS232 interface for connection to a PC or other peripheral devices.
In addition to the hardware, this project also developed the software for the two boards and Labview software for system configuration using a PC. The software supports advanced functions, such as connection by means of external control software, remote maintenance, etc.