A REDESIGNED PLASTIC CAR SEAT LEVER: INTEGRATING USER NEEDS AND TECHNICAL SPECIFICATIONS THROUGH QUALITY FUNCTION DEPLOYMENT
DOI:
https://doi.org/10.36805/v9qtf150Keywords:
Redesign, Quality Function Deployment (QFD), Seat Lever, Tensile StrengthAbstract
The automotive industry frequently struggles to strike a balance between assembly efficiency and structural strength in plastic components. PT. XYZ, a seat manufacturer, encountered this issue with their D01 car seat lever, which had a robust strength of 22.1 kgf but a lengthy assembly time of 2.5 minutes. A subsequent redesign, model D42, improved efficiency by reducing assembly time to 1.8 minutes and consolidating two parts into one. However, this new design had a critical flaw, as its average tensile strength of 16.8 kgf fell short of the required 18.5 kgf standard, making it susceptible to failure. The objective of this study was to redesign the lever to meet the 18.5 kgf strength requirement, improve assembly efficiency, and satisfy user needs with the Quality Function Deployment (QFD) method. Data was gathered from 20 respondents, including car users, technicians, and engineers, via questionnaires. The analysis showed that users prioritized durability, ease of use, accessibility, and ergonomics. The new prototype, developed using QFD principles, successfully endured a tensile force of 22.5 kgf, exceeding the safety standard and fulfilling user expectations for functionality and comfort.
Abstrak
Industri otomotif sering kali berjuang untuk mencapai keseimbangan antara efisiensi perakitan dan kekuatan struktural pada komponen plastik. PT. XYZ, produsen kursi, menghadapi masalah ini dengan tuas kursi mobil D01 mereka, yang memiliki kekuatan yang kuat sebesar 22,1 kgf tetapi waktu perakitannya lama, yaitu 2,5 menit. Desain ulang berikutnya, model D42, meningkatkan efisiensi dengan mengurangi waktu perakitan menjadi 1,8 menit dan menggabungkan dua bagian menjadi satu. Namun, desain baru ini memiliki kelemahan kritis, karena kekuatan tarik rata-ratanya sebesar 16,8 kgf tidak memenuhi standar 18,5 kgf yang disyaratkan, sehingga rentan terhadap kegagalan. Tujuan dari penelitian ini adalah mendesain ulang tuas untuk memenuhi persyaratan kekuatan 18,5 kgf, meningkatkan efisiensi perakitan, dan memenuhi kebutuhan pengguna dengan metode Quality Function Deployment (QFD). Data dikumpulkan dari 20 responden, termasuk pengguna mobil, teknisi, dan insinyur, melalui kuesioner. Hasil analisis menunjukkan bahwa pengguna memprioritaskan daya tahan, kemudahan penggunaan, aksesibilitas, dan ergonomi. Prototipe baru yang dikembangkan dengan menggunakan prinsip-prinsip QFD ini berhasil menahan gaya tarik sebesar 22,5 kgf, melebihi standar keamanan dan memenuhi harapan pengguna akan fungsionalitas dan kenyamanan.
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