Morteza Dardel
Department of Mechanical Engineering, Babol Noshirvani University of Technology, Postal Code: 47148-71167, Shariati Street, Babol, Mazandaran, Iran
[ 1 ] - Nonlinear energy harvesting through a multimodal electro-mechanical system
A semi-analytical method is used to illustrate the behavior of a multimodal nonlinear electromechanical system which is under base-excitation. System is considered as piezo-ceramic patches attached to a cantilever beam coupled to a resistive load. The cantilever beam is modeled as a nonlinear Timoshenko beam using Assumed Mode method and equations of motion are derived through Lagrange's equati...
[ 2 ] - Nonlinear Dynamics and Control of Crank-Slider Mechanism with Multiple Clearance Joints
In the current study, behavior of crank-slider mechanism with single and multiple clearance joints are analyzed. Using Lankarani-Nikravesh theory for estimating discontinuous contact forces in clearance joints, relevant systems have been mathematically modeled. Through numerical simulations, perturbations in response of mechanisms with clearance joints have been analyzed. Effects of increasing ...
[ 3 ] - بررسی تأثیر وزنی پارامترهای موثر بر ضرایب هیدرودینامیکی در طراحی پروانه‌های نیمه مغروق
شناور‌های تندروی پروازی با کاربری‌های گسترده و گوناگون تفریحی، ورزشی، تجاری و نظامی، به طور معمول دارای سرعت بالای 30 گره دریایی می‌باشند. با توجه به محدودیت‌های طراحی، به‌کارگیری سیستم نیروی محرکه در شناور‌های تندروی پروازی، یک موضوع بسیار کلیدی و حساس می‌باشد که با در نظر گرفتن ویژگی‌های مطلوب پروانه‌های نیمه‌مغروق، استفاده از آنها در سیستم پیش‌رانش این دسته از شناور‌ها، کاربرد زیادی پیدا کر...
[ 4 ] - Dynamic Behavior Analysis of a Planar Four-bar Linkage with Multiple Clearances Joint
In practice, clearances in the joints are inevitable due to tolerances, and defects arising from design and manufacturing. In the presence of clearance at a joint, a mechanism gains some additional, uncontrollable degrees of freedom which are the source of error. Moreover, joints undergo wear and backlashes and so cannot be used in precision mechanisms. In this study, the dynamic behaviour of ...
[ 5 ] - A Simple Method for Modeling Open Cracked Beam
Abstract A simple method is proposed to model the open cracked beam structures. In this method, crack is modeled as a beam element. Hence cracked beam can be assumed to be a beam with stepped cross sections, and problem of determining natural frequency and mode shape of cracked beam, can be solved as determining these characteristics for a beam with different length and cross section. With this...
[ 6 ] - Stabilization and Walking Control for a Simple Passive Walker Using Computed Torque Method (RESEARCH NOTE)
Abstract The simple passive dynamic walker can walk down a shallow downhill slope with no external control or energy input. Nevertheless, the period-one gait stability is only possible over a very narrow range of slopes. Since the passive gaits are extremely sensitive to slope angles, it is important to use a control strategy in order to achieve a wide range of stable walking. The computed to...
[ 7 ] - Crack Detection of Timoshenko Beams Using Vibration Behavior and Neural Network
Abstract: In this research, at first, the natural frequencies of a cracked beam are obtained analytically, then, location and depth of a crack in beam is identified by neural network method. The research is applied on a beam with an open crack for three different boundary conditions. For this purpose, at first, the natural frequencies of the cracked beam are obtained analytically, to get the ex...
[ 8 ] - Large Deflection Analysis of Compliant Beams of Variable Thickness and Non-Homogenous Material under Combined Load and Multiple Boundary Conditions
This paper studies a new approach to analyze the large deflection behavior of prismatic and non-prismatic beams of non-homogenous material under combined load and multiple boundary conditions. The mathematical formulation has been derived which led to a set of six first-order ordinary differential equations. The geometric nonlinearity was solved numerically using the multiple shooting method co...