TR Dizin İndeksli Yayınlar Koleksiyonu / TR Dizin Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14365/4
Browse
3 results
Search Results
Article Investigation of Backlash and Friction Nonlinearities in a 1-DoF Electromechanical System Based on Experimental Data(2025-12-25) Ertugrul, Seniz; Abedinifar, MasoudThe characterization of nonlinearities, specifically backlash and friction, in one-degree-of-freedom (1-DoF) electromechanical systems is essential for achieving high-precision control. This study presents a systematic investigation into the identification of these phenomena using a white-box modeling approach. An experimental platform, consisting of a brushed DC motor with a gearbox and a 3D-printed L-shaped load arm, was developed to generate input-output data from sinusoidal voltage excitations. A comprehensive nonlinear model, developed in MATLAB/Simulink, incorporated electrical dynamics, Coulomb and viscous friction, gravitational torque, and backlash dead-zone effects. Two complementary parameter identification methods, Nonlinear Least Squares Errors (NLSE) estimation and a Genetic Algorithm (GA), were applied to estimate the model's unknown parameters. Results demonstrated that both approaches successfully captured the dominant system dynamics; however, NLSE achieved superior accuracy in both identification (RMSE = 0.13 rad/s, R2 = 0.99) and verification (RMSE = 0.16 rad/s, R2 = 0.96) phases, compared to GA (RMSE = 0.21-0.22 rad/s, R2 = 0.94-0.97). These findings demonstrate that, with identical initialization and constraints of system parameters, a physics-based white-box model combined with NLSE provides a more reliable and precise characterization of combined backlash and friction nonlinearities than GA for the investigated 1-DoF electromechanical system and excitation conditions.Article User-Centered Approaches in Conventional and Autonomous Truck Design and Future Effects on Environmental Design(2022-04-30) Dilaver, Nimet; Küçükerman, Önder; Hasırcı, DenizMeeting the world’s increasing need for transportation today soon requires the development of autonomous vehicle systems. User-centered approaches in industrial design are crucial to advance technological, mechanical, and equipment specifications and provide effective driving experiences. This study analyzes conventional and new generation autonomous vehicles through user-centered design (UCD) and drivers’ experiences. Turkish company BMC and the new truck series “Tuğra” are selected. Participants are truck drivers, designers, engineers, and specialists. Observations and face-to-face interviews investigated comfort, usefulness, usability, desirability, accessibility, credibility, findability, and value from the elements of user experience design within the truck, as well as users’ awareness of UCD. Credibility and usability were among the highest-ranked principles. The participants provided valuable information for the design development of trucks, and ideas for future problems and solutions. Further multidisciplinary research that focuses on technical, as well as social and ethical issues is essential in this new and emerging area.Article Aerodynamic Analyses of an Integrated Low-Pressure Compression System for Adaptive-Cycle Micro Turbofan Type Jet Engine(2022-09-19) Acarer, Sercan; Gürbüz, M TayyipUnmanned Aerial Vehicles (UAVs) are commonly propeller-driven and low-speed. The concept of cost-efficient, much higher speed and longer range applications of micro jet engines was previously addressed such that an existing basic turbojet engine was converted into a single spool turbofan without using additional components of booster and low pressure turbine. Normally, this situation emerges matching problems since two spools are required to adjust the fan speed independently. A simple solution was to use a Continuously Variable Transmission (CVT) gearbox to adjust optimal speed for the fan. As a result, missing of the positive functionality of the booster would lump into the fan root to form a unified low pressure compression system (unified-LPC). Such a unified-LPC demands unique characteristics of having an extreme twist, very high pressure ratio and mass flux at the root section than at the tip section, despite the exact opposite is being enforced due to the wheel speed rise with radius. In light of these challenges, this work aims to investigate detailed aerodynamics of an existing design previously made and reported by the authors. It is shown that, despite the aerodynamic loading contrast throughout the span, the unified-LPC can still have a wide operating range and acceptable off-design aerodynamics. Complementing the previous design- oriented work, this paper aims to provide guidelines for such unified compression systems.