Study And Design Of A Travel Aid For The Blind Based On Embedded System

Travel aids have been developed to assist the blind and the visually impaired negotiate obstacle filled routes of travel in an outdoor environment. More than 70 percent of human daily activities rely on vision. If people get sight problem or lose their sights, they can't do anything at all. Therefore, travel aids are very important necessities for the blind. At present, the most popular travel aids used universally are white canes which detect obstacles by knocking ground. But knocking ground makes walking speed slow and detection missing easily. Design a new practical travel aids is very significant.The main contents in this paper are as follow:Firstly, introduced the important meaning of travel aids, present research condition and develop trend. In recent years, some laboratories start to develop a new type of travel aid called electric travel aids(ETA). Up to now, ETA is still developing and there are many drawbacks such as slow data processing, high price, and failure to detect holes etc.Secondly, the overall design of the system is given, and the principle of blind orientation and mobility training is discussed, and the requirements of the guidance system is analysed. In this work, we develop a new type of ETA, which can detect obstacles in front of a large range and provide local positioning, with good man-machine interface, low cost.Thirdly, the Principal theory of ultrasonic measurement distance and Speech signal processing technology and Man-Machine Interaction Technology are analysed and researched. Embedded system design criteria and methods were studied. Sunplus 16-bit microcontroller SPCE061A, it has a DSP function, provides Sunplus audio compression algorithm processing applications.Fourthly, we present all the circuit modules of the develop system, which include main control module, speech recognition module, serial communication module, sensor transmitter and receiver module, clock module etc.Finally, the software of this test system is developed. It include framework for the system, the primary application module, the ultrasonic distance measurement module, voice recording and recognition module. Many function such as odometer, key processing, clock display, measurement data voice broadcast have been successfully used in several research projects.