A control framework for the machining center with multiple spindlersGriparić, Karlo (Avtor) Sušanj, Diego (Avtor) Matošević, Vilijan (Avtor) Computer Numeric Control (CNC)Automatic Tool Exchanger (ATC)multiple spindlescombinatorial optimizationautomataThe paper addresses the problem of minimizing the tool exchange time in computer numerically controlled (CNC) machining centres. The increasing variety of products and the demand for smaller quantities have placed a significant pressure on the CNC systems to enhance the adaptability, improve her flexibility, and shorten the preparation and operating times. In milling machines, a certain amount of the operating time is consumed during the tool exchange process. To reduce the exchange time, the paper proposes a solution that introduces a second spindle positioned physically close to the main spindle, controlled by a pneumatic system. For this purpose a novel control framework is developed that reduces the operation time, facilitates the operator handling, and improves the efficiency. A combinatorial optimization approach is then used to solve the tool scheduling problem, in order to minimize the total exchange time of the used tools. The presented novel approach to the machine is based on the initial and final positions of each tool and on the magazine holders positions. The experimental results show that by implementing a control framework to manipulate the multiple spindles, the reduction in the exchange time is significant and dependent on the number of tools needed for a certain machining process. Moreover, the tool scheduling algorithm optimizes the tools assignment at magazine locations and efficiently reduces the total execution time. This can be important for items with a short operational time and a large number of the used tools.20252026-06-15 12:46:48Članek v reviji183571UDK: 621.9-52ISSN pri članku: 0013-5852COBISS_ID: 280485635sl