A control framework for the machining center with multiple spindlers

Griparić, Karlo (author), Sušanj, Diego (author), Matošević, Vilijan (author)

The 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.

• Language: English
• Keywords: Computer Numeric Control (CNC), Automatic Tool Exchanger (ATC), multiple spindles, combinatorial optimization, automata
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FE - Faculty of Electrical Engineering
• Year: 2025
• Number of pages: Str. 181-190
• Numbering: Letn. 92, št. 4
• PID: 20.500.12556/RUL-183571
• UDC: 621.9-52
• ISSN on article: 0013-5852
• COBISS.SI-ID: 280485635
• Publication date in RUL: 15.06.2026

Record is a part of a journal

• Title: Elektrotehniški vestnik
• Publisher: Strokovna zadruga koncesijoniranih elektrotehnikov, Elektrotehniška zveza Slovenije
• ISSN: 0013-5852
• COBISS.SI-ID: 742916

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Title: Okvir za vodenje obdelovalnega centra z več vreteni

Abstract

Clanek obravnava problem zmanj ˇ sanja ˇ casa menjave orodij v ˇ racunalni ˇ sko krmiljenih (CNC) obdelovalnih centrih. Zaradi ˇ vse vecje raznolikosti izdelkov in manj ˇ sih serij se na CNC- ˇ sisteme vrsi pritisk po ve ˇ cji prilagodljivosti, kraj ˇ semˇ casu ˇ priprave in ucinkovitej ˇ sem delovanju. Pri rezkalnih strojih del ˇ obratovalnega casa odpade na menjavo orodij, zato ˇ clanek ˇ predlaga resitev z uvedbo drugega vretena, name ˇ sˇcenega v ˇ blizini glavnega in krmiljenega s pnevmatskim sistemom. Za ˇ ta namen je bil razvit nov okvir za vodenje, ki zmanjsuje ˇ cas ˇ delovanja, olajsa upravljanje in pove ˇ ca u ˇ cinkovitost. Za raz- ˇ porejanje orodij je uporabljena kombinatoricna optimizacija, ˇ ki minimizira skupni cas menjav glede na za ˇ cetne in kon ˇ cne ˇ polozaje orodij ter polo ˇ zaje dr ˇ zal v magazinu. Eksperimen- ˇ talni rezultati kazejo, da uporaba ve ˇ c vreten in predlaganega ˇ krmilnega okvira znatno skrajsaˇ cas menjave, pri ˇ cemer je ˇ prihranek odvisen od stevila uporabljenih orodij. Algoritem za ˇ razporejanje orodij dodatno optimizira njihovo razporeditev v magazinu in ucinkovito zmanj ˇ suje skupni ˇ cas obdelave, kar je ˇ posebej pomembno pri izdelkih s kratkim obratovalnim casom ˇ in velikim stevilom uporabljenih orodij.

• Keywords: orodja za računalniško krmiljenje (CNC), obdelovalni centri, učinkovito delovanje, optimizacija, rezkalni stroji