Dynamic Analysis Based on ANSYS of Turning and Grinding Compound Machine Spindle Box

Based on the principle of axial active magnetic bearing system with single degree of freedom, the difference between magnetic system vibration mode and the traditional bearing system vibration mode were described. Initial four order natural frequencies and vibration mode were calculated by the module of modal analysis of ANSYS11. Axial displacement and control current influence on natural frequencies and vibration mode were also analyzed. At last they were compared with the results of experimental modal analysis. Analysis shows that there was a certain difference between the results of finite element method and experimental model analysis, but the difference was small. It provided theoretical basis for flexible system design and dynamic design.

Based on the principle of static and modal analysis, carry on the static and dynamic characteristics analysis to the spindle of CK61125 machine tool using the finite element method (FEM). Then, got the static stress and deformation cloud, solve the first six order natural frequency and mode shape of the structure, provides a reference of engineering design and application for the machine tool spindle.

A novel compliant mechanism with three degree of freedom (DOF) is proposed, based on the method of Freedom and Constraint Topology (FACT). One movement and two rotations are obtained in Case 3, Type 2 freedom space. A redundant constraint is added to improve the symmetry. The finite element modal (FEM) is established and static force analysis is conducted. Results demonstrate that the compliant mechanism is decoupled. Modal analysis is carried out with the finite element method. And four orders natural frequency and main vibration mode are obtained.

We theoretically investigate a new type of piezoelectric actuator with tubular interdigitated electrodes. A partial model is adopted due to the axial symmetry of the actuator, which is divided into non-overlapping opposing electrode pairs on the center plane of the branch electrode. We present a finite element model of actuator and analyze its static-dynamic properties by using the commercially available finite element software ABAQUS. The length-to-diameter ratio of the tubular actuator can be as larger as necessary, so we are more concerned with the axial mechanical properties of the actuator. Thus we studied the influence of the electrode’s shape and structure size on the clamping stress and free strain of the partial models. We also analyzed an ordinary piezoelectric model of the same size. We demonstrated that the partial model displayed significantly improved axial performance over the ordinary one. The axial stress of the partial model can reach 2.75 times that of the ordinary one, and the axial free strain can reach 1.55 times that of the ordinary one. According to the results of the static analysis, appropriate electrodes and structural parameters were selected to establish a tubular actuator model, with which modal and harmonic response analysis were performed. A modal analysis was used to obtain the frequencies and the shapes of the axial vibration. Each pair of electrodes is shunted to a sinusoidal varying voltage. Using the results of the harmonic response analysis, we obtained the actuator’s axial resonance curve.

This paper presented the dynamic characteristics and sensitivity analysis of the shaft of test machine based on finite element method and orthogonal design method.It is concluded that the top eight order natural frequencies (Hz) are 1673.3,3666.6,4421.8,5713.8,6612.9, 6656.8,9550.9, 9617.5 based on modal analysis.The harmonic analysis results indicate that the third natural frequency is more likely to intensify initiation and propagation of the bending crack on the interference joint between specimen and shaft.It is concluded that the radius dimension parameters and the length parameters affecting more greatly the dynamic characteristics of shaft are R3, R1, R2 and L3, L4, L5, L1 through dynamic sensitivity analysis.The results above provide reference for dynamic optimization and design of the shaft and other shaft parts in the future.

The principle of the magnetic levitation cylindrical linear motion guide and the theory of vibration analysis were introduced. By finite element analysis software ANSYS, modal analysis for guide was made to get the natural frequencies and vibration modes, the harmonic response analysis was also made to get the displacement response by the cutting force on the basis of modal analysis, and the influence of displacement on electromagnetic force was analysised.

Purpose To analyze the dynamic response of the lumbosacral vertebrae structure of a scoliosis spine and a kyphosis spine under whole-body vibration. Methods Typical Lenke4 (kyphosis) and Lenke3 (scoliosis) spinal columns were used as research objects. A finite element model of the lumbosacral vertebrae segment was established and validated based on CT scanning images. Modal, harmonic response, and transient dynamic analyses were performed on the lumbar-sacral scoliosis model using the finite element software abaqus. Results The first four resonance frequencies of kyphosis spine extracted from modal analysis were 0.86, 1.45, 8.51, and 55.71 Hz. The first four resonance frequencies of scoliosis spine extracted from modal analysis were 0.76, 1.45, 10.51, and 63.82 Hz. The scoliosis spine had the maximum resonance amplitude in the transverse direction, while the kyphosis spine had the maximum resonance amplitude in the anteroposterior direction. The dynamic response in transient analysis exhibited periodic response over time at all levels. Conclusion The scoliosis and kyphosis deformity of the spine significantly complicates the vibration response in the scoliosis and kyphosis areas at the top of the spine. Scoliosis and kyphosis patients are more likely to experience vibrational spinal diseases than healthy people. Besides, applying vertical cyclic loads on a malformed spine may cause further rotation of scoliosis and kyphosis deformities.

Lightweight heavy-duty CNC horizontal lathe based on particle damping materials

According to the actual needs of rehabilitation training after knee joint replacement surgery, and based on ergonomics, the idea of personification design and the basic design idea of force transfer between human body and exoskeleton are discussed, objective to develop a rehabilitation exoskeleton robot for leg rehabilitation after knee joint replacement surgery. The robot can detect the movement trend of the human body, judge the motion intention in use, and promote the movement of the hind leg, so as to achieve the purpose of rehabilitation training of the knee joint. The modal analysis of the lower limb rehabilitation exoskeleton robot is carried out, and the first six order natural frequencies and vibration modes are obtained.

In this paper, based on Ansys the deformation and stress for high pressure long cylindrical natural gas storage tank are analysed. And obtain the stress distribution of the storage tank. The changes of stress are analysed in thickness direction and along the rigid wall. The results and theoretical results are accordance. On this basis, the modal analysis of tank is completed too. Obtained the tank various order natural frequency and vibration mode. The calculation results show that the method is effective and provide the theoretical basis for high pressure tank design

Numerical analysis and physical consideration of vocal fold vibration by modal analysis

The static and dynamic performances of a machine tool structure are considered to constitute the primary factors affecting the load-carrying capacity, geometric accuracy and surface precision of the workpiece. The machining performance of a large machine tool under stable conditions is effectively determined by its dynamic response to the cutting force at low-frequency excitation. This study, therefore, investigated the static and dynamic characteristics of a large heavy-duty lathe machine tool in which the headstock and tailstock comprised critical component modules supporting a large workpiece during low-speed machining. Using a finite element model, the influences of the structural modules on the static and dynamic characteristics of the lathe were analyzed, considering the effects of the workpiece load. The results indicated that the fundamental vibration modes of the lathe were primarily dominated by headstock, tailstock, and workpiece behaviors. The maximum compliances of the lathe under the rated load were found to occur at relatively low frequencies (22, 40.7, and 82.7 Hz) and increase with the reduction in workpiece weight. Notably, these modal frequencies were significantly higher than the maximum rotational speed of the spindle (450 rpm). In addition, the dynamic rigidity corresponding to the rated speed was higher than that induced at the natural frequency. These results indicate that the subject lathe possesses sufficient capacity to sustain the cutting load during stable turning machining. This study can, therefore, help designers improve the performance of machine tools for future fabrication.

Aiming to improve the dynamic and static characteristics of a type of machining center column, the finite element modal analysis and harmonic response analysis of the column are performed, and this paper analyzes the dynamic characteristics of the column based on the first five mode shapes and natural frequencies of the column and the displacement - frequency response curves of the column. Topology optimization analysis of the column is performed with ANSYS, and the finite element analysis is performed on the column again after the column structure is improved based on the optimal distribution of material of the column structure and the design experience of column. The result shows that the first five natural frequencies of the column increase, the peak of the displacement - frequency response of the column decrease, and the dynamic characteristics are improved significantly.

The planetary transmission mechanism is the core component for realizing the maneuverability of high-speed tracked vehicles. The modal test can determine the transmission characteristics of the planetary transmission system structure, and can check whether the dynamic characteristics of the planetary transmission system meet the design requirements. It is the basis of studying the dynamic characteristics of planetary transmission mechanism. In this paper, the free mode of the planetary variable speed mechanism is tested by using the free modal test method, and the modal analysis is carried out by using the finite element method. The results show that the vibration modes of the planetary variable speed mechanism are consistent with the results of finite element simulation, and the deviation between the measured modal frequency and the simulated modal frequency is less than 2%. The modal test provides the basis for the verification of the structural dynamic model and the dynamic coupling analysis of the planetary transmission system.

In engineering domains, modal analysis is a field that is studied extensively with the goal of better characterizingcomponents or structures. Themodal analysis produces modal parameters, which are essential properties of a system that can be employed for damage identification, vibration analysis, and structural health monitoring. Plated element’s relevance in variousapplications makes it an intriguing vibration study subject. In thisresearch, modal analysis was performed on a square steel plate in free ends condition. This work aimedto provide a complete anatomical description of this complex boundary condition and its implications on modal parameters. Before comparing modal parameters with experimental data, a primary modal analysis was performed using finite element (FE)method. Then experimental analysis was conducted under the operational modal analysis setup (OMA).As the results, six natural frequencies are retrieved and compared amongst the two methods, recording the maximum of 6% percentage difference from the readings. This implied a close values estimated between the methods used. For mode shapes, ninemodes are identified from FE method and discussed according to established free plate vibration studies, while threesimilarly identified modes successfully recognized by using OMA.