Construction And Device Research Of Visual Surrogate Model Based On Lidar

At least 2.2 billion people around the world are visually impaired or blind,and nearly1 billion of them have lost their sight completely for various reasons.There are nearly 13 million visually disabled patients in China,including about 5.5 million blind people and 7.5million people with low vision.In addition,450,000 blind people and 1.35 million people with low vision are increasing every year in China.There are many blind people in every country,so it is of great practical significance to study the safe travel of blind people.Traditionally navigation systems for the blind are mainly based on ultrasonic,infrared and image algorithms.They all have their own disadvantages,such as short ultrasonic ranging distance,infrared is vulnerable to external interference,image algorithm is not mature,and laser radar has the advantages of high resolution,strong anti-interference ability,long detection distance and can still accurately locate in a weak light environment.Therefore,this design proposes a blind navigation system based on laser radar.This paper introduces the design and implementation of lidar assisted travel system for blind people in detail.Firstly,the visual substitution model was constructed,including the mathematical model of binaural intensity difference and obstacle Angle information,the mathematical model of binaural time difference and obstacle Angle information,and the mathematical model of switching frequency and obstacle distance information.Secondly,the software and hardware design of the system and the construction of the platform are introduced.The lidar sensor is used to detect the position information of obstacles,including distance and Angle.Combined with the principle of binaural positioning,the effects of Interaural Time Difference(ITD)and Interaural Intensity Difference(IID)are simulated through the left and right sound channels of earphones.The position information of obstacles is converted into sound signals and fed back to the blind.Help the blind to travel safely.Through the analysis of the experimental results,it is proved that the design scheme is reasonable and feasible,and can assist the blind to travel safely.Compared with the traditional navigation system,the performance of the system has been greatly improved,and it has great advantages in the detection range,human-computer interaction,feedback timeliness and other aspects,which has great practical research significance.