Software Design And Development Of Two-Dimensional Tactile Display System

Because of the lack of vision,blind people cannot visually and intuitively understand the physical world around them.The two-dimensional tactile display system mainly provides services for blind people to "see and understand image".The system maps information of image into two-dimensional lattices through internal processing,so that blind people can understand the information of image.At present,there are relatively few studies in the field of blind tactile image display in China.Due to the high cost,it has not yet been commercialized and cannot benefit the broad masses of blind people.This thesis aims to design a two-dimensional tactile display system with good ease of use.In the system,the design of recognition segmentation processing module which is to complete the image recognition and segmentation task is based on the YOLOv3 algorithm.After image processing,the tactile graphic display of a single object is realized in the dot matrix module.At the same time,the TTS(Text-to-speech)technology is used to implement the auxiliary voice broadcast function,so that the blind person can obtain information more conveniently.The main contents of this paper are as follows:(1)The overall design of the two-dimensional tactile display system.The system requirements and the overall framework structure are determined,and the system software and hardware design are elaborated respectively to complete the construction of the software and hardware development environment.(2)Software design and implementation of image processing module.The recognition and segmentation processing software based on YOLOv3 algorithm is designed to complete the recognition and segmentation of the captured image of the camera.Edge detection is performed on the segmented object to extract binary contour information.An optimized method of down-resolving is designed and implemented to reduce the contour information to the target resolution,which reduces the sawtooth effect of the image after the reduction.Based on Qt,the simulation simulation display interface is designed to facilitate software development and debugging.(3)Design and implementation of tactile function module.The STM32 low-power single-chip microcomputer is used as the intermediate medium for data transmission,and multi-channel I/O expansion and multiplexing are used to control the multi-module contact lifting at low cost.According to the control scheme,the corresponding serial communication protocol is designed to ensure the reliability of data transmission and realize the information interaction function between the single chip and the main control chip.The HiSi platform serial port information processing software is designed to realize data transmission through inter-process communication and complete serial port data processing.(4)Software design and implementation of voice module.The multi-threaded parallel logic framework is designed and implemented using multi-threaded programming logic.The data conversion task thread is designed based on TTS technology,and the text-to-speech data is converted and played in real time.Through the state machine query mechanism,the scheduling of the recording/playing task thread is completed,and the real-time control function for TTS voice playback is realized.