Standard Gear Research Articles

Key characteristics of generic bond graphs for planetary gears

This paper deals with generalized power flow models of compound planetary gear trains based on standard planetary gears. In this context, the Bond Graph approach provides an optimal tool for a large variety of structures. Starting with compound gears based on two standard planetary gears, two kinds of parameter definitions are discussed and two specifications for power ratio and efficiency are compared. Next, the influence of elastic shaft connections is clarified. Essential methods for these findings are the use of symmetry and the definition of sub-systems and, if applicable, of scalar or vectorial models. The second part deals with the effect of the number of constraints on constructions based on three standard planetary gears. Typical consequences, such as the number of free running elements, of complete Willis equations or of self-locking impacts, are systemized and illustrated by means of reference instances. It is shown by example that constructions featuring five external shafts would avoid such effects. Corresponding outcomes for the equivalent dynamic system equations, the parameter definitions and the Bond Graph modelling are given.

Hand-rim biomechanics during geared manual wheelchair propulsion over different ground conditions in individuals with spinal cord injury

Geared manual wheelchair wheels, a recently developed alternative propulsion mechanism, have the potential to alleviate the high upper extremity demands required for wheelchair propulsion and help decrease the risk of secondary injuries in manual wheelchair users. The objective of this study was to investigate the effects of using geared manual wheelchairs on hand-rim biomechanics of wheelchair propulsion in individuals with spinal cord injury (SCI). Seven manual wheelchair users with SCI propelled their wheelchairs equipped with geared wheels over tile, carpet, and up a ramp in low gear (gear ratio 1.5:1) and standard gear (gear ratio 1:1) conditions. Hand-rim kinetics and stroke cycle characteristics were measured using a custom instrumented geared wheel. Using the geared wheels in the low gear condition, propulsion speed (P = 0.013), peak resultant force (P = 0.005), peak propulsive moment (P < 0.006), and peak rate of rise of the resultant force (P = 0.035) decreased significantly in comparison with the standard gear condition. The significant increase in the number of stroke cycles when normalized to distance (P = 0.004) and decrease in the normalized integrated moment (P = 0.030) indicated that although a higher number of stroke cycles are required for travelling a given distance in the low gear than the standard gear condition, the low gear condition might be less demanding for the upper extremity. These results suggest that geared wheels could be a useful technology for manual wheelchair users to independently accomplish strenuous propulsion tasks including mobility on carpeted floors and ramp ascension, while reducing the risk factors contributing to the incidence of secondary upper extremity injuries.

A Novel Asymmetric Face Gear Cut by Duplex Face-Milling With Multiple Auxiliary Flank Modification Motions

Abstract Face gear sets, comprising a face gear and a cylindrical pinion, are used in the crossed axes transmission with the advantages of easy assembly and a large gear ratio. Based on the geometry of a pinion tooth flank, the tooth surface of the face gear is derived and manufactured by gear hobbing or shaping processes. However, the hobbing and shaping processes to make a face gear require special machine attachments to achieve the spatial relationship between the gear cutter and the workpiece of the face gear. These special machine attachments are not always available in a typical gear-machining factory, so this study develops a manufacturing process that uses a standard spiral bevel gear generator and standard face-milling cutting tools to produce a face gear. The productivity and the gear quality of a face gear that is made using the proposed cutting method are similar to that for a spiral bevel gear that is produced by indexed duplex cutting. The machine settings for the spiral bevel gear generator are derived using the tooth surface of a face gear, which is conjugated to the tooth surface of specific pinion. This study uses a duplex face-milling method with multiple auxiliary flank modification motions to minimize the flank normal deviation between the conjugate and the generated face gear. A numerical example and a cutting experiment are performed to verify the feasibility of the proposed methodology.

Effect of ground gear modification on bycatch of rays in mediterranean bottom trawl fishery

Bycatch of rays and skates in towed fishing gears represents one of the major threats to these relatively slow-growing marine species. The objective of this study was to modify ground gear in a bottom trawl fishery to increase the escape of these species during towing without associated loss of target catch. Sea trials were carried out with a research vessel in Mersin Bay, North-eastern Mediterranean. Experimental ground gear was modified by cutting the rigging twine between the fishing line and the footrope in the central part of the ground gear. Capture of three unwanted bycatch species were estimated. The probability of capture of guitarfish (Rhinobatos sp.) and common stingray (Dasyatis pastinaca) was significantly reduced to 8% and 20% for guitarfish and stingray, respectively compared to standard ground gear. The results for spiny butterfly ray (Gymnura altavela) were inconclusive due to the wide confidence intervals. Further, the catch comparison results for five out of six target species investigated did not show significant reduction in catch efficiency when using experimental gear compared to the standard trawl. Only for common sole (Solea solea) the modified trawl had significantly lower catch efficiency than the standard trawl. We believe that this technical measure for reducing unwanted bycatch in bottom trawls has a potential to be adopted by the fishery due to being an efficient, low-cost measure which does not create additional challenges during handling of the gear.

A Novel Inductive Angular Displacement Sensor With Multi-Probe Symmetrical Structure

This articledevelops a novel probe-type inductive angular displacement sensor based on time-grating, which is suitable for large-diameter hollow rotary table position detection of the heavy-duty machine tools. It abandons the traditional sensor precise marking lines in spatial domain, and integrates the tested mechanical component with the sensor, which realizes the angular displacement measurement directly. The sensor is divided into three parts: 1) a permalloy probe, which is adopted the simple structure to reduce the assembly errors; 2) a 45-steel rotor, which is a standard spur gear in a heavy-duty machine tool rotary table transmission system; 3) three groups of copper coils, which include sinusoidal coils, cosine coils and inductive coils. The theoretical model of angular displacement measurement is derived by means of mathematical equation in detail. Then the feasibility of the sensor structure is verified by finite element simulation. After that, a sensor prototype is built and tested in the laboratory, showing that the sensor has an original error of ±0.018° (approximately ± <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$64^{\prime \prime }$ </tex-math></inline-formula> ) over a full 360° range. The error analysis found that the systematic error is the main component. As a result, the mechanical structure and angular displacement algorithm of the sensor are optimized, which can significantly reduce the original errors of the sensor. After optimization, the final accuracy of the sensor is within ±0.0012° (approximately ± <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4.4^{\prime \prime }$ </tex-math></inline-formula> ) in the range of 0°–360°.

Nonlinear dynamic modeling and analysis of spur gear based on gear compatibility conditions

In the traditional gear dynamic model, the mesh stiffness is obtained under static load. When the mesh stiffness changes greatly with the change of load, the traditional dynamic model is not accurate enough to analyze the gear system. Therefore, this paper proposes a new dynamic model with a more realistic dynamic mesh force based on gear compatibility conditions. The proposed dynamic mesh force model is applicable to the gear system with and without tooth modification and verified by the finite element method. Afterward, the paper compares the differences in the dynamic responses between the proposed model and the traditional model. The results indicate the dynamic responses of the proposed model are generally consistent with those of the traditional model for the standard involute gear system. For the lead crown gear system, compared with the proposed model, the traditional model will lose important nonlinear characteristics in the high-speed area. At most speeds, the amplitudes of vibration and dynamic mesh force of the proposed model are greater than that of the traditional model, especially in the bifurcation, quasi-periodic and chaotic regions.

Experimental investigation on crack propagation paths in spur gears

Spur gears subjected to bending fatigue may nucleate cracks at the tooth root fillet. In thin rim gears these cracks may propagate in a safe way (through the tooth) or in catastrophic way (through the rim). Crack propagation direction is mainly influenced by both wheel geometry parameters and crack initiation point, as already pointed out by theoretical and numerical results available in literature. Aim of this work is to set up an experimental activity in order to verify the onset of the bending crack and its propagation path in spur gears with different geometries. In particular, a special device connected to a standard fatigue machine was realized to perform bending tests for both standard and thin rim gears. During bending tests, an IR thermocamera was utilized to monitor the surface thermal profile in the tooth root fillet zone.

Development of a free-form tooth flank optimization method to improve pitting resistance of spur gears

Although steel involute gears are the standard solution for gear transmissions, they tend to suffer from poor pitting resistance. Pitting typically occurs when the gear tooth flanks have high equivalent curvature at the contact point and/or when the equivalent curvature is not constant across the contact path leading to high contact pressures and the development of surface fatigue. In this paper a new optimization method is presented to produce spur gear tooth flanks with improved pitting performance compared to involute ones. The tooth flanks are represented as B-spline curves, the control points of which are the variables for the optimization problem. The constraints were designed to ensure that all the examined profiles satisfy the law of gearing and do not contain any cusps or C1 discontinuities. Deterministic and stochastic algorithms were implemented and both closed and open path of contact gear sets were examined to determine the optimum tooth profile. The optimization results show that the maximum equivalent curvature of the optimum profiles is reduced by 83% compared to the corresponding standard profiles, while the deviation from the mean value is reduced by 98%. Both the standard and the optimized gears where examined comparatively also through finite element analysis. For the case selected the maximum contact pressure developed on the optimized gear set was 77% of the respective maximum contact pressure on the standard gear set whereas the corresponding deviation from the mean value was 5%. At the same time, the bending stresses developed in the optimized gear are slightly lower than those in the standard one.

Rotor Profile Design and Motion Simulation Analysis of Hydrogen Circulating Pump

With the development of automotive fuel cells towards high power and high efficiency, higher requirements are put forward for the speed and boost ratio of hydrogen circulation pump, while high speed and boost ratio increase the pulsation characteristics and accelerate the aging of hydrogen fuel cells. Cam type hydrogen cycle pump has the advantages of compact structure, high efficiency under low boost ratio, and good adaptability to low temperature, so it has become an important research direction. The efficient and reasonable rotor profile design can improve the volumetric efficiency of the cam rotor pump. It can reduce the pressure pulsation and flow pulsation in the pump. The equation of multi-stage circular arc rotor profile is established according to the meshing principle of the rotor. Motion Simulation module in UG NX is employed to conduct dynamic interference detection of rotor mechanism and simulation analysis of rotor mechanism meshing motion on the rotating parts of the hydrogen circulating pump. So the angular velocity curve and meshing force change curve of the driven gear is obtained. In order to verify the rationality of rotor profile design, the meshing force is compared with the standard spur gear.

Sensor-integrating gears: wear detection by in-situ MEMS acceleration sensors

Gear tooth wear is a common phenomenon leading to malfunctions in machines. To detect wear and faults, gear condition monitoring by vibration is established. The problem is that the measurement data quality for detection of wear by vibration is not good enough with currently established measurement methods, caused by long signal paths of the commonly used housing mounted sensors. In-situ sensors directly at the gear achieve better data quality, but are not yet proved in wear detection. Further it is unknown what analysis methods are suited for in-situ sensor data. Existing gear condition metrics are mainly focused on localized gear tooth faults, and do not estimate wear related values. This contribution aims to improve wear detection by investigating in-situ sensors and advance gear condition metrics. Using a gear test rig to conduct an end of life test, the wear detection ability of an in-situ sensor system and reference sensors on the bearing block are compared through standard gear condition metrics. Furthermore, a machine-learned regression model is developed that maps multiple features related to gear dynamics to the gear mass loss. The standard gear metrics used on the in-situ sensor data are able to detect wear, but not significantly better compared to the other sensors. The regression model is able to estimate the actual wear with a high accuracy. Providing a wear related output improves the wear detection by better interpretability.

Trophic structure of coastal meta-ecosystems in the tropical Southwestern Atlantic

Coastal and oceanic ecosystems have their own structural and functional dynamics, but they are typically connected by the transfer of nutrients and organisms. These organic matter and energy flows mean these environments function as a meta-ecosystem. In the tropics, the transfers between estuaries and the neritic ecosystems or nearshore can be driven by estuarization events, which are poorly understood. Here, we analyze the effects of seasonal estuarization on the trophic structure of estuarine and neritic ecosystems connected by biological and physical flows in space and time. Specifically, we evaluated trophic connectivity and the flow of fish species from the South Atlantic, based on the assumption of meta-ecosystem functionality. We used standard sampling gear and fishing effort to evaluate the estuarine and neritic ecosystems during the dry and the rainy seasons of the region. The diet and trophic niche of fish species were estimated for both environments. We also reconstructed the trophic connections between species and food items for each season to evaluate the changes in the food web of each environment. During the dry season, the estuarine and neritic ecosystems are both characterized by a simpler trophic structure in terms of biomass distribution among trophic levels, but in the rainy season, the migration of species associated with estuarine and oceanic ecosystems to the neritic ecosystem changed the trophic structure of this area. The movements of organisms between ecosystems increases the complexity of the trophic structure of neritic ecosystem, allowing the transfers of organic matter and energy, confirming this complex as a meta-ecosystem.

Assessing Minnesota’s Changing Yellow Perch Populations Using Length‐Based Metrics

AbstractCatch rates of Yellow Perch Perca flavescens in standard gill‐net surveys conducted by the Minnesota Department of Natural Resources have declined since 1970, but it is unclear whether this trend was due to reduced abundance or to changes in size structure affecting catchability. Because the minimum capture length of standard gill nets may limit effective sampling of some populations, the objectives of this study were to determine if length‐based metrics could be used to characterize populations and their susceptibility to standard gill nets, if these metrics were correlated with a suite of abiotic and biotic variables, and if temporal trends in these metrics were evident. Data were collected from a broad size distribution of Yellow Perch sampled with standard gill nets, boat electrofishing, and small‐mesh gill nets in 17 lakes. Estimated length at 50% maturity (L50) for females varied up to 100 mm across lakes, with values as small as 70 mm documented in some populations. Female L50 from supplemental gears was significantly positively correlated with the average length of the 15 largest fish (Lmax) from all gears, and both of these metrics were positively correlated with standard gill‐net catch. Exploratory analysis of female L50 indicated that this metric was positively correlated with latitude and lake size and negatively correlated with water clarity. Additionally, a statewide analysis of Lmax conducted with standard gill‐net data from over 1,000 lakes found significant declines during the past 25 years, indicating that populations in Minnesota have likely shifted towards a smaller size structure, reducing catchability in standard gill nets. These results indicate that standard gill nets were ineffective for sampling some Yellow Perch populations and that length‐based metrics such as L50 and Lmax can be used to infer catchability in standard gear and to monitor populations through time.

Optimization of Profile Shift Co-efficient for Highest Contact Ratio in Non-standard Gearing

The power transmission in mechanical drives is undoubtedly handled by gears. Tooth profile of a gear characterizes the power transmission. Standard gears mostly employ involute tooth for reasons of simplicity, while non-standard gears employs involute tooth profile shifting either positive or negative to modify the tooth geometry. Profile shifting is practiced in two ways, first known as S-gearing, either S0 or S± without change in tooth-sum while the second known as Altered tooth-sum gearing, aptly called Z± gearing with change in tooth-sum Zs, tooth-sum being the sum of teeth on pinion and gear. In S± gearing the center distance will change while in S0 gearing and Z± gearing the center distance remains unchanged. Altered tooth-sum gearing is a novel method of increasing (Z+) or decreasing (Z-) the tooth-sum of standard gearing either by adding or removing one or more teeth (±Ze) in either pinion or gear or both and eventually distributing the resulting total profile shift co-efficient among the gear pair, thus maintaining the same center distance. In designing Non-standard gearing the amount of profile shift is expressed as ‘Xm’, where ‘X’ is known as Profile shift co-efficient and ‘m’ is module of the gear. This has a significant influence on the gearing in terms of load carrying capacity, contact ratio (CR), load sharing etc. In this study contact ratio of altered tooth-sum gearing is focused, as it affects the tooth load sharing with influence on vibration and noise levels as well. Optimization of the profile shift co-efficient will be meaningful in designing gears to give highest contact ratio. Load sharing is observed to be beneficial in Altered tooth-sum gearing using increased tooth-sum (Z+ gearing), besides this method offering unparallel benefits to gear engineering.

Effects of modification on the strength–weight ratio of standard bevel gears

Because of the current rapid technological progress, in addition to achieving increased speed and momentum in machine, transmitting more power in a low-noise, lightweight, safe, and economical manner and saving material in gears is crucial. For this purpose, modified bevel gears are common. Therefore, this study investigates bevel gear profile modifications focusing on strength and raw material saving. Herein, three modification designs (Modifications I–III) were modeled using CATIA software. Finite element analysis (FEA) and experimental tests were performed to investigate the effect of the proposed modifications on the gear’s strength. Design and analysis procedures of the modifications were presented. Prototypes of the modified gear pairs were fabricated and subjected to strength and wear tests using a dynamic test device. The fatigue life of each gear pair was determined using nCode software. Modification II reduced the gear root stress by 3.98% relative to the original gear pair. Modification III resulted in 37.30% material saving, accompanied by 6.74% increase in contact stress. No fatigue damage was detected in either modification gear pair. The FEA results were compatible with the analytical, i.e., KISSsoft simulation, and experimental results; furthermore, FEA was found to be advantageous in terms of time and test costs in gear modification. Based on the obtained results for the three modifications, the Modification II gear pair is recommended for mass production.

Carry along or not? Decision-making on carrying standard avalanche safety gear among ski tourers in a German touring region

Ski touring is a winter sport activity that enjoys increasing popularity. Recreationists practice it exclusively without using ski lifts in the backcountry, where conditions continuously and rapidly change, and avalanche danger exists. Ski tourers can increase their own and others’ avalanche survival chances, among others, by carrying standard avalanche safety equipment (i.e., transceiver, probe, and shovel). Recent studies among backcountry recreationists identify various aspects to influence the decision to ‘carry or not’ this equipment by testing each factor individually for its statistical significance for the decision. This explorative study, in contrast, applies a new methodological approach and considers ‘carry or not’ as a decision process. The analysis bases on the behavioral decision theory and uses the machine learning algorithm decision tree to illustrate the decision process and examine the relative importance of each influencing feature. Therefore, we conduct a researcher-administered survey (n = 359) among ski tourers in a German touring region. According to their carrying behavior, this study classifies ski tourers into three different types: weather-oriented, complex, and conformist. Conformists always carry the avalanche equipment and are known in research. Weather-oriented ski tourers, who predominantly base their decision on environmental conditions (i.e., avalanche danger level and weather), are as new as the complex type, which relies on various features. In contrast to previous findings, personal traits play a subordinate role in the decision process of any type. Furthermore, we interpret environmental aspects in decision-making as decision heuristics that awareness-raising measures and education programs need to address.

The effect of machined wheel profile geometry on cutting force

The mechanisms based on standard geometry gears have reached their technological limits. To meet the needs of the market, it is necessary to meet new and new, often conflicting operational requirements. At the same time, it is necessary to reduce the mass of the node and increase the maximum torque, in addition, the noise level and increase the axial load must be reduced. To achieve the increasing requirements for the operational characteristics of mechanisms gears with specially designed tooth geometry are used. A tool for cutting such gears must be specially designed and manufactured for each new gear pair, given into account its design features. The introduction of a new tool in the technological processes of machining gear profiles leads to the fact that the surface quality decreases and tool wear increases. At present, the concept of this problem is scattered and composed of the experience of individual researchers. The work reveals the dependencies connecting physical phenomena accompanying the cutting process and the geometric parameters of the profile of the bevel gear. Based on the results of the project, it is possible to calculate the optimal profile parameters based on the technological parameters of the process.

Evaluating the fishery of tropical reservoirs using surplus production models: A case study of Aliyar Reservoir, Tamil Nadu, India

AbstractReservoir fisheries support the livelihood needs of socio‐economically deprived fishers and ensure the nutritional security of rural populations. To sustain community food safety and economic needs, a basic understanding of the prevailing biological and economic conditions, as well as a comprehensive evaluation of the fishery is essential. To this end, the present study focused on evaluating the fisheries of the small Aliyar Reservoir located in the Coimbatore District of the state of Tamil Nadu, India, utilizing surplus production models. The maximum recorded fish catch was 51.3 MT in 2015, with the minimum catch of 10.89 MT obtained in 1991, and the average production during 1985 to 2018 being 30.80 MT from the reservoir. The peak catch season was during the months of February to May. The MSY (Maximum Sustainable Yield) and other key fish population parameters, including the carrying capacity (K), catchability coefficient (q), intrinsic population growth rate (r) and coefficient of variation (CV), using catch and effort data (CEDA) analysis and ASPIC (a surplus production model incorporating covariates) computer software packages. Using CEDA software, the estimated MSY was 36.92 MT (CV = 0.47) using the Fox model and 36.68 MT (CV = 0.307) using the Schaefer model. An integrated surplus production model (CYP) of Clarke et al. (Marine Research Economics, 1992, 7, 115) was also fitted to the data and found to be the best fit with the MSY, an estimated optimum effort of 51.20 MT and 5110 nets/year. The results indicated the need for increasing the fishing effort with appropriate standard gears for exploiting the fish stock. Further economic optimization with the CYP model indicates increasing the fishing effort by 34% will lead to a 40% increase in the annual profits for the fishermen.

Perioral Aerosol Sequestration Suction Device Effectively Reduces Biological Cross-Contamination in Dental Procedures.

Objective The infection risk during dental procedures is a common concern for dental professionals which has increased due to coronavirus (severe acute respiratory syndrome coronavirus 2) pandemic. The development of devices to specifically mitigate cross-contamination by droplet/splatter is crucial to stop infection transmission. The objective of this study is to assess the effectiveness of a perioral suction device (Oral BioFilter, OBF) to reduce biological contamination spread during dental procedures. Materials and Methods Forty patients were randomized 1:1 to a standard professional dental hygiene treatment with OBF and without. Adenosine triphosphate (ATP) bioluminescence assay was used to evaluate the spread of potential contaminants. The total number of relative light units (RLU) from key dental operatory locations: operator’s face-shield, back of the surgical operator’s-gloves, patient’s safety-goggles, and instrumental table were measured. Percentage contamination reductions between control and OBF were compared. Statistical Analysis Primary outcome, total RLU, was analyzed by comparing the means of logged data, using a two-sided two-sample t -test. Secondary outcomes as RLU of logged data for the different locations were analyzed in the same way. Proportion of patients from whom different locations reported events (clean, acceptable, and failure) were analyzed by using Fisher’s exact test. Results For the whole dental environment, RLUs reduction (<150 units) achieved with OBF was 98.4% (97.4–99%). By dental operatory location the reduction in RLUs was from 99.6%, on the operator face-shield, to 83% on instrumental table. The control group reported a very high percentage of failures, (>300) being 100% on the surfaces closer to the patient’s mouth and decreasing to 70% on instrumental table. In contrast, the higher failure percentage in the OBF group was found on the patient’s goggles (40%), while the operator face-shield showed an absence of contamination. Conclusion OBF device has shown efficient reduction of biological aerosol cross-contamination during dental procedures as proved by ATP-bioluminescence assay. Nevertheless, for maximum safety, its use must be combined with standard protective gear such as goggles, face shield, and surgical gloves.

Gear Shape Measurement Potential of Laser Triangulation and Confocal-Chromatic Distance Sensors

The demand for extensive gear shape measurements with single-digit µm uncertainty is growing. Tactile standard gear tests are precise but limited in speed. Recently, faster optical gear shape measurement systems have been examined. Optical gear shape measurements are challenging due to potential deviation sources such as the tilt angles between the surface normal and the sensor axis, the varying surface curvature, and the surface properties. Currently, the full potential of optical gear shape measurement systems is not known. Therefore, laser triangulation and confocal-chromatic gear shape measurements using a lateral scanning position measurement approach are studied. As a result of tooth flank standard measurements, random effects due to surface properties are identified to primarily dominate the achievable gear shape measurement uncertainty. The standard measurement uncertainty with the studied triangulation sensor amounts to >10 µm, which does not meet the requirements. The standard measurement uncertainty with the confocal-chromatic sensor is <6.5 µm. Furthermore, measurements on a spur gear show that multiple reflections do not influence the measurement uncertainty when measuring with the lateral scanning position measurement approach. Although commercial optical sensors are not designed for optical gear shape measurements, standard uncertainties of <10 µm are achievable for example with the applied confocal-chromatic sensor, which indicates the further potential for optical gear shape measurements.

A Multiobjective Optimization Analysis of Spur Gear Pair: The Profile Shift Factor Effect on Structure Design and Efficiency

Spur gears are an indispensable element of power transmission, most of the time used in small environments with severe operating conditions such as high temperature, vibrations, and humidity. For this reason, manufacturers and transmission designers are required to look for better gear designs and higher efficiency. In this paper, a multiobjective optimization was conducted, using genetic algorithms (GAs) for corrected spur gear pair with an objective to reduce the structure volume and transmission power loss and reveal the influence of the profile shift factor on the optimal structure fitness. The optimization variables included are the pinion and wheel profile shift factors in addition to the module, face width, and the number of pinion teeth mostly used in standard gear optimization. The profile shift factor influences the shape of the gear teeth, the contact ratio, and the load sharing. It affects then the optimal results meaningfully. The gear pair volume, center distance, and efficiency presented the objective functions while contact stress, bending stress, face with coefficient, and tooth tip interferences served as constraints. Furthermore, a volume equation was developed, in which a bottom clearance formula is included for more accurate results. "Multiobjective optimization" is conducted at medium and high speeds, and the results show that the structure design is compact compared to standard gears with reasonable efficiency for medium contact ratio.