Based On The Fingers Of The Aerodynamic Load Mechanical Response Study

Tactile information can enhance the realistic sensation and construct the immersion in virtual reality system. The tactile feedback system is an essential choice, for which needs smart operation, multi-degree of freedom and perception of grip status and material information of objects in the application of virtual assembly, remote operation and virtual surgery. However, current research in haptic display is just starting and has many deficiencies simultaneously. Related studies show that the human tactile perception is a dynamic behavior. Finger and nozzle finite element models are established in the paper. Mechanical response and deformation of the finger under pneumatic dynamic load are analyzed, which provide a direct reference to the design of pneumatic haptic interface device.The main research contents are as follows:(1) In order to analyze the factors affecting the finger tactile information, the three-dimensional nonlinear finite element model of the fingertip and finite element model of the nozzle are established. In addition, characterization parameters evaluating tactile sensations are also built.(2) Mechanical response of fingertip under different loads is researched by numerical simulation methods. Firstly, Finger mechanical response to the single point dynamic load is analyzed, and the changes of finger response under different frequency, amplitude, carrier and waveform are compared, which builds the foundation for research in multi-point dynamic loading. Then the finger response under multi-point static load is studied. The effects of nozzle diameter, nozzle interval and pressure on line haptic are analyzed. The range of different parameters which can preferably realize line haptic is given. Finally the finger response under multi-point dynamic loads is analyzed. The factors which influence finger mechanical response are compared through pressure frequency, amplitude, carrier, phase difference, nozzle diameter and nozzle interval.(3) The finger deformation measurement experimental table is built, and related measurement and experiment are completed. Firstly, the sensitive frequency which fingers can feel is measured. Different people’s deformation under the same load is measured, and the difference between the responses of diverse human finger is analyzed. Secondly, the viscoelastic properties of the finger skin are verified by experiment. Thirdly, the finger deformation under single point dynamic load is measured and compared with the finite element analysis results from different pressure amplitude, carrier and waveform. Fourthly, the finger deformation under multi-point static and dynamic load is measured and compared with the finite element analysis results. Lastly, line and sliding haptic display experiments are carried out. The experimental results indicated that line and sliding haptic display can be easily achieved through reasonable regulation of the parameters of nozzle structure and pressure.