Research On The Design, Preparation And Application Of Artificial Skin Tactile Sensors

With the development of science and technology,smart sensors have received more and more attention.In this paper,a self-made liquid core PVDF(polyvinylidene fluoride)piezoelectric fiber is used as the artificial material of artificial skin.Artificial skin based on flexible tactile sensors is an electronic device that can sensitively sense the surface pressure of objects and the surface roughness of objects.It can be affixed to the surface of the object to achieve the tactile properties of the object.Therefore,it has a very wide range of applications in smart robots,wearable electronic devices and other fields.The specific content mainly includes the following four aspects:First,the hollow fibers were prepared using PVDF materials and home-made equipment,and the conductive liquid was injected.Fine stainless steel wires were introduced into the fibers and the conductive silver paste was externally sprayed.The stainless steel wire acts as an electrode and the conductive silver paste acts as an electrode to complete the preparation and extraction of the electrodes on the fiber surface.After polarization,a single liquid core fiber acts as a piezoelectric sensor.The cross section of the fiber was analyzed by scanning electron microscopy and the effect of fiber diameter on the sensitivity of the artificial skin was experimentally analyzed.Second,according to the first type of piezoelectric equations,the theoretical sensing model of PVDF piezoelectric fiber with cantilever beam structure is established,the sensing mechanism of liquid core PVDF piezoelectric fiber is studied,and a piezoelectric test platform is constructed for piezoelectricity of artificial skin.Performance and sensitivity are tested.The response signals of the same fiber at different positions,the response signals of the fiber to different distances,the thickness of the artificial skin,and the output response signals were analyzed experimentally.Third,the artificial skin is applied to the robot's finger,and the ability of the artificial skin to perceive the surface roughness of the object and the perceived resolution of the artificial skin are tested through an experiment in which the artificial skin perceives the protrusion height of the object surface and an experiment of sensing the groove width of the object surface.The relationship between the finger weight and the speed of the touched object surface and the output response signal was experimentally studied.Fourth,study the basic dynamic strain sensing performance of artificial skin.Analyzed the equivalent model of the artificial skin in the bending state and the corresponding piezoelectric equation,and stimulated the acrylic plate through the exciter to drive the deformation of the artificial skin.The output waveforms of the artificial skin and the laser displacement sensor were measured and recorded.The low frequency characteristics of the artificial skin,the artificial skin response time difference,and the strain sensing characteristics of the artificial skin under different frequency and different amplitude load excitations were studied.