Gear Arrangement Research Articles

Numerical Simulation and Experimental Validation of Planetary gearbox System Design to Govern Constant Generator Speed in Hydro Power Plant

Micro Hydro Power Plant (MHPP) is a clean and renewable source of harnessing power ranging between 5kW-100kW. The reservoirs are avoided in MHPP and power house is directly placed in the path of the water stream. In India, there exists an abundant resources unutilized due to technical constraints. As the flow of the water stream varies, the input velocity of turbine also varies and so does the generator speed. Hence, the challenge lies in arriving at a gear arrangement to maintain constant generator speed. In the present paper, an auxiliary gearbox with planetary gearbox is designed to maintain constant generator speed for various input turbine speed. Based on these specifications, the planetary gear and auxiliary gearbox is designed through analytical calculations. The complete system is modelled to carry out Multi Body Dynamic simulation to verify kinematic analysis (analytical method) and FEA to analyse stresses developed in planetary gearbox system. The auxiliary unit and planetary gearbox is fabricated and tested for no load condition to maintain the constant generator speed. The test results are found to be close agreement when validated with the analytical method and multi body dynamic simulation results. Hence the designed system is practically feasible for maintaining constant generator speed for fluctuation turbine speed

Determination of Natural Frequencies of Spur Gear in Portal Axle Gearbox

Portal axle is introduced to avoid damage of the vehicle bottom portion while it is running on off-road condition by providing additional ground clearance to the vehicle. Since the ground clearance is achieved through gear train arrangement, the operating frequency of the gear shouldn’t match with its natural frequency. This work aims to predict the natural frequencies and modes shapes of the gear train with three types of gear arrangements. The effect of natural frequency also studied with three different gear materials such as steel, CI and Al alloy. Gear trains are modeled in Solidworks 2017 and analyzed in well-known FEM software ANSYS workbench 16.0. First six natural frequencies and corresponding mode shapes are also obtained. FEM results are compared with operating frequency of the gear

Controlling The Variac Through Arduino With Remote Access Control Using The Stepper Motor

In this paper being presented, we propose designing the controlling system using an Arduino Uno microcontroller board for an auto-transformer attached to a permanent magnet stepper mechanism. We can create a control model by employing a stepper motor regulated with an Arduino Uno board. In the presented method of Arduino plug-in contrsol-based design, altering between states is attained by event triggering or provisional modification like a manual operator input which is maintaining the probable voltage output in autotransformer. The system involves the interconnection of drivers to the stepper motor connected to the autotransformer with the help of gear arrangement. The stepper motor was controlled through an Arduino Uno microcontroller board and as per the program requirements as per the application output through variac. The Arduino is fueled by a battery and a LED is linked for its indication.

Design of Solar Power LED Lighting System using Horizontal Two-Axis Arduino Based Solar Tracking System

The project deals with design of solar power LED lighting system using Horizontal Two-Axis Arduino based Solar Tracking System. The main goal of this project is to design a very precise solar tracker. The project is divided into two parts; hardware and software. Hardware part generally composed of solar panel, two-DC motors with gearbox, LDR sensor module and electronic circuit. Software part represents the thinking behavior of the system, that is how the system acting under several weather conditions. In this work sensing of the sun position carried out in two stages primary and secondary. Primary stage or indirect sensing performed via sun-earth relationship as a coarse adjustment and second stage or direct sensing performed via set of LDR sensors as output tuning to trims the azimuth and altitude angles. If the weather is cloudy or dusty, the tracking system uses primary stage or sun-earth geometrical relationships only to identify the location of the sun; so the system tracks the position of the sun regardless the weather condition. The energy extracted from photovoltaic (PV) or any solar collector depends on solar irradiance. For maximum extraction of energy from the sun, the solar collector panel should always be normal to the incident radiation Solar trackers moves the solar collector to follow the sun path and keeps the orientation of the solar collector at an optimal tilt angle. Solar tracking system improves substantially the energy efficiency of photovoltaic (PV) panel. In this paper, an automatic dual axis solar tracking system is designed and developed using Light Dependent Resistor (LDR) and DC motors on a mechanical structure with gear arrangement. Two axis solar tracking (azimuth angle as well as altitude angle) is implemented through Arduino UNO controller based on Sun Earth Geometry. The results indicated that the automatic solar tracking system is more reliable and efficient than fixed one.

Investigation of nonlinear landing gear behavior and dynamic responses on high performance aircraft

The dynamic responses simulation of aircraft as rigid body considering heave, pitch, and roll motions, coupled onto a tricycle landing gear arrangement is presented. Equation of motion for each landing gear consists of un-sprung mass vertical and longitudinal motions considering strut nonlinear stiffness and damping combined with strut bending flexibility. Initially, the nonlinear dynamic response model is subjected to an input of riding over staggered bump and the responses are compared with linear landing gear model. It is observed that aircraft dynamics and important landing gear events such as vertical, spin-up and spring-back are truly represented with nonlinear stiffness and damping model considering strut bending flexibility. Later, landing response analysis is performed, with the input from nonlinear flight mechanics model for several vertical descent rate cases. The aircraft and landing gear dynamic responses such as displacement, velocity, acceleration, and reaction forces are obtained. The vertical and longitudinal drag forces from the nonlinear dynamic response model is compared with “Book-case method” outlined in landing gear design technical specifications. From the reaction force ratio calculation, it is shown that for lower vertical descent rate case the predicted loads are lesser using nonlinear dynamic response model. The same model for higher vertical descent rate cases predicts higher ratios on vertical reaction for main landing gear and longitudinal reaction for nose landing gear, respectively. The scope for increase in fatigue life for low vertical descent rate landing covering major design spectrum and the concern for static strength and structural integrity consideration for higher vertical descent rate cases are discussed in the context of event monitoring on aircraft in services.

Improving operational characteristics of wave gears

The advantage of wave gears is a possibility to obtain greater transmission ratios in one stage. The main drawback is a short life of a flexible gear due to large deformations with cyclically changing stresses. The proposed technical solution provides using a roller chain instead of the flexible gear. The gear arrangement is similar to a two-wave gear in which there is a wheel used instead of the flexible gear, with each tooth of it consisting of three rollers located in axial alignment. Middle row rollers are located along the edge of the master jaw. The outermost row rollers of the located along the lesser diameter of the jaw come into external engagement with two immobile gear wheels which have the number of the teeth equal to the number of the chain rollers. As a result, the chain does not rotate. The outermost row rollers that are located along the greater diameter of the jaw come into internal engagement with the follower wheel. At the cost of the differences of the follower wheel teeth and the chain rollers, the motion transmission occurs. The supposed transmission arrangement allows providing a transmission ratio in one stage up to 6 and higher that reduces the dimensions of the actuator.

An Application of Elliptical Trammel For The Purpose of Bottle Shaking

This presented article is an approach towards the use continuous motion of double sliders of crank chain mechanism which is automated by applying AC motor and gear arrangement as a Bottle shaking Machine. This is an elliptical trammel mechanism in which two sliders moves in to two slots, imparting perpendicular motion to each other. A connecting rod is used to connect these two sliders and make the motion constrained. The slotted Lever is mounted part within the mechanism. Two sliders, a crank and a connecting rod are the various components of mechanism and relative motions of these components are described having degree of freedom as a unity. Design of mechanism has been performed on the basis of their dimensions and deformation. Analysis of various components of the mechanism has been carried out. Thus this an elliptical trammel from which the approximate straight motion of sliders is being used for shaking purpose of bottles.

Antikythera mechanism – A compound epicyclic gearing for Venus

One undeniable characteristic of Antikythera mechanism is the complex gear arrangements that generously have been used by the constructor. He succeeded the best combination of integer numbers to reach the maximum accuracy, no matter the number of the gears he used for it. One representative example is the “moon train” consisted of eleven meshing gears which he used to simulate the non-uniform lunar motion. Someone could say that the constructor preferred the complexity for the sake of accuracy. Many Scholars, believe that the mechanism could be a kind of planetarium. In that case, there is a possibility of a more complex mechanical subsystem comprised of more imaginative and specialized gear arrangements. The latest decoded inscriptions on the mechanism's surfaces, are referred to planets (Inferiors and Superiors) and show records of astronomical events. The lack of physical evidence of this planetary construction prevents its conception, but on the other hand, challenges the researchers to discover the inimitable thought of its creator. Nevertheless, fitting this excess gearing in a limited space of a compact construction like Antikythera mechanism is really a puzzler. The planetary subsystem which will complete the mechanism should stand out for the maximum possible measurement accuracy and the best space management. This research proposes a feasible epicyclic gearing specialized for a compact planetary construction achieving the highest possible accuracy.

Design, Fabrication and Analysis of Automatic Telescopic Mount

The major advantage of the project is the ease with which a celestial body may be tracked in the night sky. This gives us access to proper imaging and exploring new systems in the night sky. The telescope has an 8’ aperture .This is achieved by attachment of worm-worm gear arrangement mounted of the shafts of the RA and Dec axes of the telescopic mount. To this a controlling system using PLC programmed with PLC language is used which is controlled by using an HMI. The project aims to have high accuracy and precision in object tracking. A Nema 23 Stepper motor with a 4.25 reduction gearbox has been selected. This arrangement is controlled by a 24V SMPS and 48V DC power supply. The project is economically affordable thus making it more available to the local enthusiasts.

Extended horn gears in 3D maypole braiding

This article presents the theoretical background for the arrangement of horn gears in maypole braiding machines in order to act as equivalent larger gears. The theoretical analysis is verified with numerical simulation and experiments. After review about the state of the art, an analysis of the process for one specific configuration of horn gears is given. This analysis demonstrates how a set of horn gears can be arranged to work as an equivalent to a larger one horn gear. The braiding equation is checked as remaining valid for such extended configurations, too. The theoretical result is verified using numerical simulation for all cases and practical validation for several variants. The theoretical rules give a clear extension of the current braiding knowledge and make the design of complex configurations of braiding machines more systematic and clear.

Modified Screw Jack for Lifting Operation in Industrial Setting

With the increasing level of technology, researchers all over the world are working continuously to improve and implement better and robust design of materials at workplace for productivity, efficiency and effectiveness. Detailed design procedure of a quick lifting screw jack is presented in this paper. The design is fundamentally a modification of the conventional scissor jack. The problems associated with the conventional jacks are the ergonomic snags experienced by operators due to prolonged bending or squatting positions during operation. These problems of waist pain and backaches are as a result of continuous turning of the wrench or crank shaft in an uncomfortable position for a long period. These led to the design and modification of quick lifting screw jack with gear arrangements that are safe, reliable and capable of raising or lowering heavy load with little effort. The results showed that the introduction of the crank and gear mechanism would help reduce difficulty in operation, reduce time, increase efficiency and effectively control the difficulties concomitant with Ergonomics - which is an ultimate sensitivity in design process.

Modified Screw Jack for Lifting Operation in Industrial Setting

With the increasing level of technology, researchers all over the world are working continuously to improve and implement better and robust design of materials at workplace for productivity, efficiency and effectiveness. Detailed design procedure of a quick lifting screw jack is presented in this paper. The design is fundamentally a modification of the conventional scissor jack. The problems associated with the conventional jacks are the ergonomic snags experienced by operators due to prolonged bending or squatting positions during operation. These problems of waist pain and backaches are as a result of continuous turning of the wrench or crank shaft in an uncomfortable position for a long period. These led to the design and modification of quick lifting screw jack with gear arrangements that are safe, reliable and capable of raising or lowering heavy load with little effort. The results showed that the introduction of the crank and gear mechanism would help reduce difficulty in operation, reduce time, increase efficiency and effectively control the difficulties concomitant with Ergonomics - which is an ultimate sensitivity in design process.

ANALYSIS OF THE DYNAMIC BEHAVIOUR OF MULTI-MESH SPUR AND HELICAL GEARS - APPLICATION TO THE DEFINITION OF OPTIMUM PROFILE RELIEFS IN AERONAUTICAL TRANSMISSIONS

This paper is focused on the modelling and analysis of vibrations and dynamic loads in aeronautical multi-mesh gears comprising several spatial gear arrangements (idler gears, several pinions on one shaft. Optimum profile modifications are sought by applying a metaheuristic Genetic Algorithm to the local quasi-static transmission errors under load associated with each individual mesh. It is shown that the resulting linear symmetric profile modifications all lie in the vicinity of the so-called analytical Master Curves initially defined for a single pinion-gear pair. The theory is applied to a 6-mesh aeronautical transmission and it is found that the proposed profile modifications can effectively reduce dynamic overloads and improve the vibrational behaviour of complex multi-mesh gears with different power circulations. Finally, it is shown that for systems submitted to several load levels, short optimal reliefs seem preferable with regard to vibration levels.

内歯車のスカイビング加工用テーパカッタ設計に関する研究(ピ二オンカッタに用いる台形砥石での創成通し研削によるテーパカッタ)

Taper shaped skiving cutters are commonly used in gear skiving because they provide clearance angles under a simple gear arrangement and they could have lower cutting resistance than cylindrical skiving cutters. Their tooth flanks are generally ground by the same method of generation grinding with a trapezoidal wheel as ones for pinion cutter tooth flanks for gear shaping. In gear skiving, however, the process of tool-face re-grinding could increase profile deviations of cut gears due to the lack of an appropriate change in cutter profiles along the facewidth. In the present paper, computer programs were developed to simulate the generation grinding and the skiving with the cutting edges ground by the method. Skiving with a cutter ground by the method were carried out and skived tooth forms were compared with those calculated by the developed program. As a result, the comparisons could guarantee the reliability of the program. Furthermore, the program has revealed that the increase in a helix angle of a cutter yields the increase in tooth profile deviations of skived gears after regrinding the tool faces. Therefore, taper shaped cutters should be applied to internal gear skiving with extra caution.

A Geometrical Modular Design for Handling of LPG Cylinders using Nested Kinematic Robotic Gripper

Objectives: Novel design of Robotic gripper by means of epicyclic gear arrangement and incorporation of this mechanism for quick and efficient handling of domestic LPG gas cylinders from supplier end to consumer end. Methods/Statistical Analysis: Many researchers and robot manufacturing companies highly concentrate the new design of grippers and invent the smart grippers which is operated by means of efficient mechanisms and advanced techniques. In this paper discusses the modular design of a new robotic gripper operated by means of the epicyclic gear arrangement. Findings: Presently, domestic fuel LPG cylinders are loaded and unloaded manually from trucks. Loading and unloading LPG cylinders is involving lots of labour and sometimes cause finger crush and other disability to the personnel. This invention is particularly useful in unloading and unloading of empty and filled gas cylinders from vehicles such as trucks in a desired pattern and ensures safety and efficient handling. A geometrical model is developed and this device is helpful to a large extent for the handling of LPG cylinders meant for domestic purpose and this device will serve for the quick disposal of LPG cylinders to the consumers and safety of personnel is considered. Automation of this device may lead to higher investment. To meet the low capital investment, this device has to be partially mechanized. Application/Improvements: Epicyclic gear train is used for speed reduction purpose only. In this novel design, actuation of grippers is made possible by placing a suitable gripper in the planet gears. Gripper is mounted in planet gear eccentrically. This gripper is specially designed for loading and unloading the domestic LPG cylinders from trucks. Grippers are arranged in a required pattern for bulk handling of Large number of LPG cylinders. Locking and unlocking of grippers with LPG cylinders is mechanised in a supporting frame.

Analysis and design of a dynamic gear testing apparatus using high stiffness thermo-hydraulic actuators

Dynamic gear testing has always produced controversial results since the testing apparatuses and measuring methods have failed to distinguish the eigen-behaviour of the gear-pair from vibrations coming from the inevitable excitation of shafts, housing-parts and other ancillary equipment. Numerical techniques for separating and identifying the gear-mesh signal from the acquired data have been developed, although this procedure requires specialised software tools and can only be implemented in special cases involving rigid gear arrangements. Nevertheless, this is not always feasible, as it is when the gear shafts need to be rotated in space to simulate positioning and assembly errors resulting in misalignment. In this work, a novel ultra-rigid thermo-hydraulic actuator design is proposed to use in a laboratory gear test rig able to quantify, control and reliably measure the dynamic characteristics of misaligned cylindrical gear-pairs in mesh. A comparative study over existing actuation solutions and a thorough eigen-frequency numerical analysis highlight the unique potential of the proposed design.

Development of small scale frustum cone shaped butter churn

A novel small scale improved butter making unit called 'Frustum Cone Shaped Butter Churn was developed with working capacity of 5 liter curd/batch. This paper deals with development of parts of churn i.e. inner and outer frustum cone, stirring tube, head and closure and insulation etc. For better insulation foamed polyethylene was used to offset the effect of ambient on temperature of curd filled inside the churn. For controlling the speed of the motor, gear and pulley arrangement with v-belt was used. The highest overrun and yield of butter were recorded to be 24.41 per cent and 1.63 kg/5 l. curd at higher churning temperature of 12°C and higher churn speed of 85 rpm. However, the optimum speed of churn for good quality butter production was found to be 60 rpm at churning temperature of 10°C.

DEVELOPMENT OF 3-SPEED REAR HUB BICYCLE TRANSMISSIONS WITH GEAR-SHIFTING MECHANISMS

Rear hub bicycle transmissions require less maintenance and are more reliable than rear derailleurs. This study proposes a systematic design process for the conceptual design of 3-speed rear hub bicycle transmissions. By analyzing the kinematics of a basic epicyclic gear mechanism using the fundamental circuit method, the gear sequence and clutching sequence arrangements for 3-speed rear hub transmissions can be obtained. The numbers of gear-teeth for all gear elements resulting in a minimum installation space and satisfying the required speed ratio at each gear stage are determined. A gear-shifting mechanism is constructed to sequentially control the power-flow path within the epicyclic gear mechanism so as to provide three forward gears. An atlas of 3-speed rear hub bicycle transmissions is listed, where three devices are new design concepts and are suitable for further embodiment design. The results of this study will lead to the creation of new multi-speed rear hub bicycle transmissions.

Failure analysis of axle shaft of a fork lift

An axle shaft of fork lift failed at operation within 296h of service. The shaft transmits torque from discrepancy to wheel through planetary gear arrangement. A section of fractured axle shaft made of induction-hardened steel was analyzed to determine the root cause of the failure. Optical microscopies as well as field emission gun scanning electron microscopy (FEG-SEM) along with energy dispersive spectroscopy (EDS) were carried out to characterize the microstructure. Hardness profile throughout the cross-section was evaluated by micro-hardness measurements. Chemical analysis indicated that the shaft was made of 42CrMo4 steel grade as per specification. Microstructural analysis and micro-hardness profile revealed that the shaft was improperly heat treated resulting in a brittle case, where crack was found to initiate from the case in a brittle mode in contrast to ductile mode within the core. This behaviour was related to differences in microstructure, which was observed to be martensitic within the case with a micro-hardness equivalent to 735HV, and a mixture of non-homogeneous structure of pearlite and ferrite within the core with a hardness of 210HV. The analysis suggests that the fracture initiated from the martensitic case as brittle mode due to improper heat treatment process (high hardness). Moreover the inclusions along the hot working direction i.e. in the longitudinal axis made the component more susceptible to failure.

Analysis and simulation of Wiseman hypocycloid engine

AbstractThis research studies an alternative to the slider-crank mechanism for internal combustion engines, which was proposed by the Wiseman Technologies Inc. Their design involved replacing the crankshaft with a hypocycloid gear assembly. The unique hypocycloid gear arrangement allowed the piston and connecting rod to move in a straight line creating a perfect sinusoidal motion, without any side loads. In this work, the Wiseman hypocycloid engine was modeled in a commercial engine simulation software and compared to slider-crank engine of the same size. The engine’s performance was studied, while operating on diesel, ethanol, and gasoline fuel. Furthermore, a scaling analysis on the Wiseman engine prototypes was carried out to understand how the performance of the engine is affected by increasing the output power and cylinder displacement. It was found that the existing 30cc Wiseman engine produced about 7% less power at peak speeds than the slider-crank engine of the same size. These results were concu...