Research On Haptic Rendering Based On Electromagnetic Field Control

As an emerging technology of human-computer interaction,haptic rendering uses haptic interfaces and virtual environment created by PC to enable users to perceive,touch and manipulate virtual objects actively.Haptic rendering then leads to a more realistic and immersive virtual reality system and deserves significant research.Tranditional tool based haptic devices cannot meet the need of natural human-computer interaction,which will influence haptic perception.Therefore,this paper studies non-contact haptic rendering based on electromagnetic field control.To produce effective electromagnetic interaction force,generation and control principles of electromagnetic field are analyzed first.The finite element tool ANSYS is used to analyze the two solenoids of "solenoid" and "helmholtz like",and relationships between electromagnetic force of permanent magnet and coil current and spatial position are given.The spatial position of human hand is required in the haptic rendering system,so the position detection method based on Microsoft Kinect is studied.The whole scheme of haptic rendering display based on electromagnetic field control is designed according to the theoretical analysis results of electromagnetic field.The hardware scheme mainly includes the electromagnet module which generates the one-dimensional electromagnetic field,the wearable glove module with magnets,the human hand position detection module based on Kinect,the central control module based on Intel NUC,the electromagnet control module based on TM4C1294 micro controller,the electromagnet drive module based on SA306 A chip and so on.The software programs include the human hand position detection based on Kinect,the PWM drive and control of the coil current,the serial communication between NUC and embedded microcontroller,coil current ADC acquisition and so on.In order to generate the effective one-dimensional electromagnetic force,a force control method based on ANSYS simulation data is proposed.The method determines the relationship between the electromagnetic force and the coil current in each position of space.Then,the parameters of the haptic device are tested,including the system response time measurement experiment,the depth distance calibration experiment,the electromagnetic field and the electromagnetic force measurement experiment.The results show that the local maximum feedback force the device can supply is 13.49 N,the response time of the local maximum feedback force is 40 ms,and the position detection precision and resolution are 2mm and 1mm respectively.To verify the effectiveness of the haptic rendering system,the general interface driver of the haptic device is designed,and a three-dimensional pattern recognition experiment and the perception experiment of flexible objects are carried out based on CHAI3 D tool.The experimental results show that our system can be applied as a universal haptic device and obtains a high success rate to the perception of virtual objects based on haptic rendering.In this paper,the research of haptic rendering based on electromagnetic field control is studied in many aspects,including theoretical analysis,hardware and software design and perception experiments,which lays an important research foundation for the study of non-contact and natural haptic rendering.