Bevel Gears Research Articles

Tooth surface mismatch design of cycloidal bevel gear based on two directions modification of pinion cutter

Tooth surface mismatch design of cycloidal bevel gear based on two directions modification of pinion cutter

A Linkage-Driven Underactuated Robotic Hand for Adaptive Grasping and In-Hand Manipulation

The development of robotic hand that can imitate human movements has always been an important research topic. In this paper, a linkage-driven underactuated three-finger hand is proposed to imitate the flexion/extension (f/e) and abduction/adduction (a/a) motions of human hand. The robotic hand has three identical underactuated fingers, each of which contains an underactuated planar linkage, a spherical four-bar mechanism, and a set of bevel gears. The spherical four-bar mechanism is designed to provide 2-degree-of-freedom actuation, driving the f/e and a/a motions of the proximal joint simultaneously. Based on screw theory, the kinematic model of the spherical mechanism is established, and the maximum available workspace index (MAW) of the spherical mechanism is proposed to evaluate the workspace with the same adduction and abduction angle ranges. The effects of the parameters of the spherical mechanism on the MAW and the transmission efficiency are obtained, and the parameters of the spherical mechanism are optimized. The optimization results show that the MAW of the spherical mechanism can be increased by up to 3.5 times. Finally, experiments are carried out to show the proposed robotic hand can perform simultaneous adaptive grasping and in-hand manipulation. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —The robotic hand is of great significance for replacing workers in heavy, repetitive, and unsafe working environments. Uncertain environments in non-manufacturing fields, such as industries for pick-and-place, sorting, palletizing, assembly and other operations, marine development, and medical service, require that robotic hands can operate tasks like human hands. Inspired by the human hand with the f/e and a/a motions, a linkage-driven underactuated three-finger hand is proposed in this paper to imitate the functions of the human hand. Due to its underactuated characteristics and a/a function, the designed robotic hand is more dexterous and economical. The effects of the design parameters of the spherical mechanism on the MAW and the transmission efficiency are analyzed, and the parameters of the spherical mechanism are optimized to improve the performance of the robotic hand. This approach can be used in other industrial applications related to the robotic hand or the spherical mechanism.

A method to manufacture spiral bevel gears by equivalent completing

As a transmission part for industrial application the manufacture of spiral bevel gear is particularly important. The present machining methods for manufacturing spiral bevel gears, including the so called five-cut method and completing method, have drawbacks such as low processing efficiency, requiring complex calculations and high requirements on the machine-tool performance, respectively. To solve the above problems, an equivalent completing method is proposed to process spiral bevel gear in this paper. Firstly the machine setting parameters by completing were translated from the Cradle-type hypoid generator to Cartesian-type hypoid generator and the workpiece is swing during process. CNC motion axes expression of Cartesian-type hypoid generator were expressed as sixth-order polynomial, the influences of coefficient on the tooth surface topology were researched. Then the method to machine spiral bevel gear was put forward by reducing the swing axis of workpiece, obviously a deviation of tooth surface was caused between theoretical and axis-reduced. As a response, a flank correction model was established and the other polynomial coefficients were adjusted to eliminate the deviation. Finally simulation and cutting experiment were carried out by a numerical example. The experimental results show that the proposed method is effective and feasible. The method proposed in this paper overcome and enrich the disadvantages of existing manufacture methods of spiral bevel gear.

Investigation of non-uniformity of temperature distribution and phase transformation in spiral bevel gears during carburizing and quenching

Investigation of non-uniformity of temperature distribution and phase transformation in spiral bevel gears during carburizing and quenching

Heme-substituted protein assembly bridged by synthetic porphyrin: achieving controlled configuration while maintaining rotational freedom.

The use of biological host-guest interactions, specifically the binding of hemoprotein to heme, has attracted significant research interest in the design of artificial protein assemblies. However, because of the inherent flexibility of the propionic acid group of heme, it is difficult to control the positioning and orientation of the protein unit and to construct well-ordered structures. Herein, we report a heme-substituted protein dimer composed of the native hemoprotein HasA, which accommodates a tetraphenylporphyrin bearing an additional metal coordination site. The specific binding of the tetraphenylporphyrin with an additional metal coordination site that protrudes in a fixed direction confines the configuration of the dimer structure to a defined bent form. The small-angle X-ray scattering profile shows the dimer structure with a bent form and suggests dynamic rotational behavior while keeping its bent-core structure, resembling a bevel gear. This unique dimer structure demonstrates that the design of heme-substituted protein assemblies can be expanded to protein assemblies while maintaining the rotational freedom of the individual protein units.

Influence of cut parameters on mesh performance of spiral bevel gear by duplex spread blade method

Spiral bevel gears are key components in many mechanical transmission systems, and their production is always of great interest to industry, and hence, subjected to intensive research widely. The present machining methods for manufacturing spiral bevel gears, including the so called five-cut method and completing method, have drawbacks such as low processing efficiency, requiring complex calculations and high requirements on the machine-tool performance, respectively. To solve the above problems, the duplex spread blade method is proposed. Firstly, geometric parameters and machine setting parameters were comprehensively considered, and then a modified reference point was selected to deduce the machine setting parameters. Tooth contact analysis (TCA) model considering misalignment was established to check meshing performance, the influence of cutter parameters and misalignment on meshing performance was studied. As the research reveals that the cutter radius has an effect on the bias of contact trace, cutter number has an impact on the position of contact pattern. The experimental results are consistent with the theoretical which verified the effectiveness and feasibility of the proposed method. The results of this paper have a guiding significance and enrich the machining method for spiral bevel gear.

Targeted tooth surface predesign and machine-tool settings identification methodology of spiral bevel gear considering ease-off

Targeted tooth surface predesign and machine-tool settings identification methodology of spiral bevel gear considering ease-off

Simulative optimization of continuous bevel gear manufacturing with special regard to effective tool angles

In recent years, extensive research has been carried out on the influence of tool and process design on tool wear for bevel gear cutting. However, due to the complex interactions between tool, gear and process design, an analytical analysis of the cutting process has proven difficult. In this paper, the influence of the tool design on tool wear in continuous bevel gear manufacturing is analyzed using both simulations and cutting trials. Initially, a theoretical analysis is performed using a manufacturing simulation and a method is derived to calculate the effective tool angles. Subsequently, the results of cutting trials using the same tool designs are presented and compared to the simulation results.

Process and tool design optimization for hypoid gears with the help of the manufacturing simulation BevelCut

Catastrophic tool wear, active clearance sides of the tool and resulting fins at the tooth’s root are among the undesirable phenomena that can occur when cutting bevel gears. So far, these obstacles to manufacturing could not be predicted during the design phase. This paper presents an approach to identify critical process and tool designs using the manufacturing simulation BevelCut. Based on the simulation results, the occurrence of cutting phenomena is correlated to the characteristic values and corrective measures are deduced. Finally, the effectiveness of the corrective measures is assessed by comparing the characteristic values of the original and optimized design

Reverse Engineering for Real Tooth Surfaces of Generated Spiral Bevel Gears

Reverse Engineering for Real Tooth Surfaces of Generated Spiral Bevel Gears

Study on cutting force calculation and optimization strategy of machining spiral bevel gear by using forming method

Study on cutting force calculation and optimization strategy of machining spiral bevel gear by using forming method

One way to improve the quality of a medical manipulator for sterile boxes

Today, the advanced robot-surgeons and medical manipulators are managed by operators. Among the best recognized systems are: Da Vinci, Robodoc, SMR Surgical Versius. Further development of medical robotic surgery field requires new solutions in the engineering and software spheres. The main issues and directions are remote surgical operations online as well as automation of processes in sterile boxes. To overcome such limitations, the system must be of minimal size, but it should not lose its accuracy and power. A large number of solutions are aimed at a specific characteristic: Robodoc (accuracy and automation), Da Vinci (flexibility and remote control), SMR Surgical Versius (modularity and miniaturization). If the system has high accuracy, small dimensions and the possibility of automation, it will significantly accelerate the development of robotic surgery.&#x0D; This task can be solved by removing all electronic components from the segments of the manipulator. Such a solution is already available in the robot surgeon Da Vinci, but a cable mechanism is used there at the base of the segments, which does not allow automating the process because of a low accuracy. The solution that will ensure sufficient accuracy and allow automating the processes is using a bevel gear inside the segments. In this way, it is possible to reduce significantly the size and to increase the accuracy (enlarging the number and type of motors), as well as to make the system as modular as possible, which in its turn will simplify the repair and maintenance.&#x0D; A manipulator prototype was developed and printed on the NodeMcu hardware platform. The main functionality corresponds to the task. The dimensions of the prototype are 324x324x620 mm, but at the same time, like Da Vinci's robotic surgeon, 7 degrees of freedom remained. Nema17 motors have been used, the accuracy has increased significantly and reaches more than 0.01mm Automation research is still ongoing, but the vibration rate has been significantly reduced because all the motors are placed separately. Technical solutions will allow automating work in sterile boxes, ensuring maximum reliability.

Development and Realisation of an Electrically Actuated Lifting Apparatus Employing Bevel Gear Kinematics

Development and Realisation of an Electrically Actuated Lifting Apparatus Employing Bevel Gear Kinematics

Soft-stable interface in grasping multiple objects by wiring-tension

Efficiently manipulating objects in a group state poses an emerging challenge for soft robot hands. Overcoming this problem necessitates the development of hands with highly stable structures to bear heavy loads and highly compliant designs to universally adapt to various object geometries. This study introduces a novel platform for the development of robot hands aimed at manipulating multiple objects in each trial. In this setup, the objects come into soft contact with an elastic wire affixed to the finger skeletons. This combination results in a harmonious hybrid finger, inheriting both the soft, flexible properties of the wire and the robust stability provided by the finger skeleton. To facilitate this approach, a theoretical model was proposed to estimate the kinematics of manipulating multiple objects using wiring-based fingers. Based on this model, we designed a hybrid gripper comprising two wiring-based fingers for conducting experimental evaluations in manipulating four groups of samples: a pair of bevel gears, a pair of bevel gears plus a pneumatic connector, a pair of glue bottles, and a pair of silicon bottles. The experimental results demonstrated that our proposed gripper reached good performance with high success rates in durability tests conducted at various lifting velocities and high adaption with objects in soft-friendly ways. These findings hold promise for efficiently manipulating multiple complex objects in each trial without the need for complex control systems.

Calculation of the deformation values of the ammortizer in the compound angle gear transmission

The article presents the method of calculating the axial deformations of the rubber bush used in the bevel gear with the recommended composition and the formulas for determining the axial deformations. Based on the analysis of the connection graphs, the recommended values of its parameters were determined. The article presents the results of an analysis of the design features and disadvantages of cylindrical gears. An effective design scheme for a helical cylindrical gear transmission with elastic elements has been developed, allowing it to absorb peak values of oscillations of torques and axial force components arising from the meshing of wheel teeth, as well as cycling noise indicators.

Research on a hybrid modeling method of a spiral bevel gear based on cutter simulation

Research on a hybrid modeling method of a spiral bevel gear based on cutter simulation

Consideration of the Optimal Form of Rib by Observing the Stress and the Tooth Deflection of a Small and High-Strength Spiral Bevel Gear Fabricated Using Five-Axis Controlled Machining Center

Consideration of the Optimal Form of Rib by Observing the Stress and the Tooth Deflection of a Small and High-Strength Spiral Bevel Gear Fabricated Using Five-Axis Controlled Machining Center

Analysis of Failure Forms of Bevel Gear, Shaft, and Bearing Structure System Considering Multi-Mode Damage Accumulation

Abstract During the working process, the structural system, including bevel gear, shaft, and bearing, located in the front journal of the high pressure compressor of the aeroengine rotor is affected by various loads such as assembly load, centrifugal load, temperature load, and meshing excitation, and it leads to different modes of interface damage, for example, wear, slip, and fatigue. With the increase number of working cycles, different interface damage modes affect each other and damage gradually accumulates, which leads to the degradation of the mechanical properties of each component. Finally, the function of the weakest component is lost, resulting in the failure of the structural system. Consequently, the comprehensive influence of multiple failure forms caused by interface damage at different positions results in the failure of the structural system, where the damage position and the failure position are different, and the final failure form is uncertain. In this paper, a damage accumulation mechanical model considering multimode damage interaction is established for bevel gear, shaft and bearing structure system. And the damage-failure mechanical process of the structural system and its key influencing factors under complex environment loads are studied. The results showed that the failure forms of the structural system were closely related to the assembly and load characteristic parameters of the components. Therefore, considering the randomness of the initial assembly state and environment loads, the damage accumulation mechanical process and the final failure forms of the structural system have significant uncertainty.

Influence of assembly errors on meshing characteristics of spiral bevel gear and compensation approach of misalignment

Based on the spatial position relationship of spiral bevel gear, mathematical model and mesh model applied with finite element analysis (FEA) approach has been established. The influence of axial position errors of pinion and wheel, offset error, and shaft angle error on the meshing characteristics has been investigated. A method has been proposed to compensate the gear assembly errors by the axial displacement of the pinion and wheel, and the correctness of this method verified by numerical examples. The performed results indicate that the existence of assembly errors can cause contact pattern on the tooth surface to deviate from its design position, resulting in poor meshing quality and having a certain impact on transmission error (TE) and peak-to-peak transmission error (PPTE). The pinion and wheel’s axial positioning errors can be offset by each other, whereas the offset error and shaft angle error can be mitigated by the interplay between the axial positioning of the pinion and wheel. By compensating for assembly errors with axial displacement, the position of the contact pattern can be precisely controlled, and TE will not significant changes.

A dual-kinetic energy harvester operating on the track and wheel of rail deceleration system for self-powered sensors

Alternative energy sources play a crucial role in Outback rail systems, where electrical infrastructure is unavailable for automated power devices used for traffic lights, surveillance cameras, sensors, and other safety equipment at railway stations and intersections. The current study proposes an innovative dual-kinetic energy harvester design to reduce train speed at intersections and before it comes to a halt at the station. Additionally, it harvests energy from both the train track and wheel simultaneously. The proposed device consists of three main units. The first unit utilizes vibrational movement based on a rack pinion. An efficient dual-kinetic energy harvesting system has been developed, utilizing a novel concept that captures the vibration energy generated by the movement of the rail under the influence of the train’s weight. Additionally, as the train passes at high speed, the train wheel’s energy will be transmitted to the top of the device, moving the rack to a depth of 30 mm. A spiral spring is employed to restore the rack to its initial position after the wheel has passed. The tension force of the spring causes the rack to adhere to the track, enabling the transmission of vibrations generated by the track’s movement and releasing energy, causing the motion to be induced during the return stroke. The second component is the transmission unit. The bidirectional rotational motion from the rack pinion is converted into unidirectional rotational motion using three bevel gears, two roller clutches, and a planetary gearbox to enhance the rotations of the generator shaft. The third component is a 1500 W/180 V DC motor for electricity generation. Lastly, the charging circuit was developed to recharge supercharged capacitors. The proposed system was installed before the railway station, and practical tests were conducted, which showed an efficiency of up to 55%.