Feasibility study ure5 Collaborative robot at engine piston assembly station Abstract

Feasibility study URe5 Collaborative robot at engine piston assembly station
Abstract.
The trend toward collaborative robots becomes more common in the motor vehicle powertrain assembly operations because current collaborative robots ensure the physical safety of humans during close proximity in assembly operations. This interaction promises capability flexibility due to human dexterity skills and capacity flexibility due to robot accuracy. However, particularly when engine piston assembly operations are considered, the process requires an increased amount of flexibility and precision, and employees often overstress over a long period of time. Therefore, this paper aims to answer the question of whether collaborative robots (cobots) are suitable for engine piston assembly applications in motor vehicle engine assembly lines. In order to answer this question, a case study is conducted where the integration of collaborative robots is assessed and compared to the current state, which is performed manually. To specifically answer the question, engine piston assembly station was mapped using the hierarchical task analysis (HTA) method in order to statistically identify the effective time of each value-added task within the assembly operation. Then a new station layout was recreated with a collaborative robot in RoboDK simulation software to measure how much time is needed to complete the robot task. The rest is tested in laboratory condition with the URe5 collaborative robot to compare the mean effective process times of manual, hybrid, and simulation operations.
Keywords: Cobots, Assembly systems, piston,

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   Introduction (Ikrom)
   

Industrial robots have been widely employed in tasks such as welding, material handling, painting and non-ergonomic repetitive tasks[ CITATION Zha07 \l 1033 ]. However, recent application of the lightweight collaborative robots (cobots) becoming more frequent in assembly operations because they promise the physical safety of humans during close interaction in assembly operations[ CITATION Ali19 \l 1033 \m Dra10]. Many researchers argue in their researches that, the interaction of human and cobots in assembly operations ensures capability flexibility due to human dexterity skills and capacity flexibility due to robot accuracy[ CITATION Kam22 \l 1033 ]. The following Figure 1 represents key motivations of cobots integration into assembly operations[ CITATION Bau16 \l 1033 \m Scm17 \m Kam22].


Fig 1. Key motivations cobot integration into assembly operations
Nevertheless, the systematic literature analysis showed that, the engine piston assembly is one of the most challenging assembly processes, because it requires an increased amount of flexibility, precision, and assembly operators often overstress over a long period of time[ CITATION Zha07 \l 1033 \m Dav08]. To deal with this complicated engine piston assembly process, human and robot piston assembly technology must be studied systematically. Therefore, this paper aims to answer the question of whether cobots are suitable for engine piston assembly applications in motor vehicle engine assembly lines. In order to answer this question, this paper is organized as follow: Section 2 demonstrates mapping, simulation and testing (MST) methodology used in order to analyze feasibility of cobots into engine piston assembly systems, Section 3 is verification process of proposed methodology by case study implementation, Section 4 is intended for analyses results and discussions and finally Section 5 depicts conclusion and future work of the paper.

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