Final Assembly Testing Research Articles

An Overview of the Engine Remanufacturing Process Based on Independent Remanufacturers in Malaysia

The automotive remanufacturing industry is the largest remanufacturing sector, accounting for around two-thirds of global remanufacturing activities. Engine parts are a common target for remanufacturing due to their high value and demand. With the introduction of the National Automotive Policy (NAP) 2020 in Malaysia, many small and medium-sized enterprises (SME) are progressively taking part in the remanufacturing industry, especially engine remanufacturing. However, since the remanufacturing process is more complex than the primary production of the same products, challenges partaking in the operations and processes of remanufacturing are common in the industries, especially for independent remanufacturers. There still lacks data that shows the process flows of these engine-remanufactured products being conducted locally. In this study, a qualitative interview has been conducted through focus group discussion (FGD) with the SMEs to determine the processes and practices for automotive remanufacturing, thereby identifying key components of engine remanufacturing. Four different category questions, accompanied by several sub-questions to determine the processes and methods in their aspects of automotive remanufacturing, have been asked. The findings show that engine remanufacturing is a series of intricate processes being done carefully and extensively, from the cleaning process to the final assembly testing for which varies heavily depending on the components and industries. While the remanufacturing processes across the independent remanufacturers are almost the same, findings also suggest there exist additional processes that can be applied to increase the lifespan of the products, such as additive remanufacturing techniques, that these independent remanufacturers know but do not apply to their processes due to the cost and economics of the business. Further research exploring case studies of these independent remanufacturers is recommended to ensure a more holistic and critical aspects of engine remanufacturing to be captured.

FBG displacement sensor with hyperbolic flexible hinge structure

This paper proposes a design method for a fiber Bragg grating (FBG) displacement sensor with a hyperbolic flexible hinge structure. A compact FBG displacement sensor with strong micro displacement measurement capability was fabricated. The final assembly testing showed that the sensor achieved good linearity with a linearity of 0.53%F·S at a range of 50 mm. The sensitivity was measured as 24.45 pm mm−1, hysteresis error as 1.1%FS, and repeatability error as 0.659%. The testing results demonstrated that the fabricated FBG displacement sensor exhibited strong practicality and good stability, making it suitable for long-term displacement monitoring of slope safety.

Robot trajectory planning for autonomous 3D reconstruction of cockpit in aircraft final assembly testing

The trend towards automation and intelligence in aircraft final assembly testing has led to a new demand for autonomous perception of unknown cockpit operation scenes in robotic collaborative airborne system testing. To address this demand, a robotic automated 3D reconstruction cell which enables to autonomously plan the robot end-camera's trajectory is developed for image acquisition and 3D modeling of the cockpit operation scene. A continuous viewpoint path planning algorithm is proposed that incorporates both 3D reconstruction quality and robot path quality into optimization process. Smoothness metrics for viewpoint position paths and orientation paths are introduced together for the first time in 3D reconstruction. To ensure safe and effective movement, two spatial constraints, Domain of View Admissible Position (DVAP) and Domain of View Admissible Orientation (DVAO), are implemented to account for robot reachability and collision avoidance. By using diffeomorphism mapping, the orientation path is transformed into 3D, consistent with the position path. Both orientation and position paths can be optimized in a unified framework to maximize the gain of reconstruction quality and path smoothness within DVAP and DVAO. The reconstruction cell is capable of automatic data acquisition and fine scene modeling, using the generated robot C-space trajectory. Simulation and physical scene experiments have confirmed the effectiveness of the proposed method to achieve high-precision 3D reconstruction while optimizing robot motion quality.

Research on the design of massive weight satellite transfer platform

The new generation of the DFH-5 platform satellite independently developed by China has been successfully launched by CZ-5 launch vehicle in Hainan satellite launch center. Up to now, the satellite has been running smoothly with good functions and services. It is the heaviest satellite launched in China with the highest technical content. In this paper, a kind of transfer platform is designed to meet the transfer requirements of heavy satellites such as the East five platform. The transfer platform is composed of body frame, omni-directional wheel set, console, battery, electric control system, etc. The transfer platform has the functions of independent control, safety detection, accurate positioning, human-computer interaction, etc. through analysis and calculation, the ultimate compression and anti-overturning performance is stable and reliable, meeting the needs of satellite and other tooling during the final assembly test. Then it can reduce the risk of assembly operation and improve the efficiency of assembly test.

Towards an Energy Efficient Series Production of High Performance Permanent Magnet Synchronous Motors by Selective Magnet Assembly

When installing magnets on synchronous rotors, the target values of energy efficiency, vibration, noise emissions, power density and synchronism are decisively influenced by the quality of the rotor magnetic field. This depends on the real position of the magnets after mounting, on the polarization of the magnet and on the direction of magnetisation. However, large component tolerances in the magnet bodies also require tolerances in the rotor magnetic field. The quality assurance in the field of rotor production, which is largely lacking in the current state of the art, is compensated for by robust motor designs in order to keep the rejects low. Unconventional machine designs, such as the Halbach arrangement of the magnets, exploit optimization potential in terms of power density by eliminating the ferromagnetic component in the rotor and reduce harmonics due to the almost sinusoidal field shape, so that more efficient winding processes, such as linear winding in the stator with a constant low torque ripple compared to distributed winding, are used. At the same time, however, the requirement for homogeneity of the magnetic field increases due to the matching pairing of the magnets and the correct magnetic position when using sintered, isotropic rare earth magnets. By 100 % testing of magnets and rotors, it is possible on the one hand to exploit these design potentials and on the other hand to estimate the performance data of the motor before the final assembly test by means of data mining. In the framework of the E|MagTol project, the process feasibility of a logistics solution for storing magnetized goods has already been successfully investigated. In order to extend the potential uncovered in the previous project, it is necessary to record all process data of the rotor assembly process such as magnet geometry, magnet position, polarization and magnetization direction. The aim of E|S2MART is on the one hand to increase machine efficiency by compensating for component deviations by adapting or matching the magnetic position and magnetic parameters in a closed-loop control loop in the assembly process and on the other hand to significantly increase the energy efficiency of the assembly process. This is done by optimizing the magnetization process and coupling with inductive heating to replace the furnace process during the bonding process and to reduce the energy consumption during magnetization. On the basis of the existing process experience, the savings potential in the assembly process is estimated to be at least 70 % compared to conventional processes.

A 50 kW PEMFC Pilot Plant Operated with Industry Grade Hydrogen – System Design and Site Integration

AbstractThe chlor‐alkali industry produces high amounts of hydrogen as a by‐product of processes based on electrolytic cells. In order to improve the process' efficiency, plant operators seek ways to utilize this potential and fuel cells offer a sensible solution, producing electricity at high efficiency. PEMFC has already been demonstrated to be successful in this niche market application with a few commercial scale installations. In the DuraDemo project, a 50 kW stationary PEMFC pilot plant has been designed in a publicly funded national project involving partners from different parts of the value chain. The plant serves as an experimental platform for evaluation of BoP and power electronics components, as well as hydrogen quality studies. The system design is targeted to be commercially viable and a large amount of extra instrumentation and experimental monitoring equipment are utilized in the pilot plant to analyze its behavior. The pilot plant is fully automated and capable of independent operation with remote monitoring and data logging capability. The system design of the pilot plant is presented, including BoP component selection and characterization of the main components. Final assembly testing results, integration of the plant at its demonstration site and safety analysis work will be reported.

IBM System z9 eFUSE applications and methodology

IBM System z9TM is the first zSeries® product to use electronic fuses (eFUSEs). The blowing of the fuse does not involve a physical rupture of the fuse element, but rather causes electromigration of the silicide layer, substantially increasing the resistance. The fuse is with the application of a higher-than-nominal voltage, eFUSEs provide several compelling advantages over the laser fuses they have replaced. The blow process does not risk damage to adjacent devices, eFUSEs can be blown by a logic process instead of a physical laser ablation method, eFUSEs are substantially smaller than laser fuses, and they scale better with process improvements. Finally, since no specialized equipment or separate product flow is required, eFUSEs can be blown at multiple test and application stages. We discuss circuit design, fuse programming, test considerations, and z9TM system applications. The physical and logical implementation of eFUSEs has resulted in improved yield at wafer, module, and final assembly test levels, and has provided additional flexibility in logic function and in system use.