GUIDED MICROCONTROLLER FOR BLIND PEOPLE

With the development of radar and ultrasonic technologies, when combined with the robotic technology and bioengineering, gave rise to new series of devices, known as “electronic travel aids (ETAs). It operates similar to a radar system, sends a laser or an ultrasonic beam, which after striking the object reflects back and is detected by the sensors, and so the corresponding distance from the object is calculated. In particular, these devices are used to help people organ failure and people with disabilities, such as visual impairment, deafness etc. This paper is about an instrument, which is the outcome of robotics and bioengineering, and it is called “Guided Microcontroller”. It is a robotics-based obstacle-avoidance system for the blind and visually impaired. A device, called Guided Microcontroller, uses the mobile robotics technology is a wheeled device pushed ahead of the user via an attached cane. When the Guided Microcontroller detects an obstacle, it steers around it. The user immediately feels this steering action and can follow the device’s new path easily without any conscious effort. I. INTRODUCTION This paper is about “GUIDED MICROCONTROLLER (Guide Cane)”, which is computerized device based on advanced mobile robotic navigation for obstacle avoidance useful for visually impaired people. This is “Bioengineering for people with disabilities”. The Guided Microcontroller uses the mobile robotics technology is a wheeled device pushed ahead of the user via an attached cane. When the device detects an obstacle, it steers around it. The user immediately feels this steering action and can follow the device’s new path easily without any conscious effort. The mechanical, electrical and software components, user machine interface and the prototypes of the device are described below. II. MOBILE ROBOTICS TECHNOLOGIES FOR BLIND PEOPLE With the development of radar and ultrasonic technologies, a new series of devices, known as Electronic Travel Aids (ETA’s) was developed. Obstacle Avoidance Systems (OAS) originally developed for mobile robots; lend themselves well to incorporation in Electronic Travel Aids for the visually impaired. An OAS for mobile robots typically comprises a set of, ultrasonic or other sensors and the computer algorithm that uses the sensor data to compute the safe path around detected obstacle. One such algorithm is the Vector Field Histogram (VFH). The VFH method is based on information perceived by an array of ultrasonic sensors (also called Sonar’s) and a fast statistical analysis of that information. The VFH method builds and continuously upgrades a local map of its immediate surroundings based on recent Sonar data history. The algorithm then computes a momentary steering direction and travel speed and sends this information to the mobile robot. The ultrasonic sensors are controlled by the Error-Eliminating Rapid Ultrasonic Firing (EERUF) method. This method allows Sonar’s to fire at rates that are five to ten times faster than conventional methods. In the VHF method, the local map is represented by a two-dimensional (2D) array, called a Histogram Grid. The 2D Histogram Grid is reduced to a one-dimensional Polar Histogram that is constructed around the robot’s momentary location. The Polar Histogram provides an instantaneous 360˚panoramic view of the immediate environment, in which elevations suggest the presence of obstacles, and valleys suggest that the corresponding directions are free of obstacles. The Polar Histogram has 72 sectors that are each 5˚ wide. The numeric values associated with each sector are called Obstacle Density Values. Figure (1), shows the Polar Histogram created from an actual experiment, wherein, high Obstacle Density Values are shown as taller bars in the bar chart type representation. Hence, the Polar Histogram provides comprehensive information about the environment (with regard to obstacles).