Performed by:david eyal tayar yosi Instructor: miki itzkovitz המעבדה למערכות ספרתיות מהירות High speed digital systems laboratory הטכניון - מכון טכנולוגי לישראל הפקולטה להנדסת חשמל Technion - Israel institute of technology department of Electrical Engineering דו ” ח סיכום פרויקט ( סופי ) Subject: Electronic guiding cane סמסטר חורף 4\2003 1

Abstract המעבדה למערכות ספרתיות מהירות High speed digital systems laboratory 2 The electronic guiding cane is designed to provide a more accurate guiding tool for the blind, than the existing laser guiding cane. The electronic guiding cane will alert its user of objects in front of him, with estimation for the distance to it. The electronic guiding cane will identify objects above the ground, that might be in the users way (should cover a little more then the users entire height ). Alerts its user by vibrations, according to the distance from the object.

System description המעבדה למערכות ספרתיות מהירות High speed digital systems laboratory 3 The electronic guiding cane uses Infra-Red & Ultra-Sound sensors. The Ultra-Sound circuit is made of two US transmitters and two US receivers that produce a high accuracy distance measurement. The Infra-Red sensor is a complete module that measures the distance, and products voltage level accordingly. The measurements are inserted into amplification circuits for filtering and amplification. The measurements are inputted into the PIC microprocessor for processing, and the distance is calculated according to the two measurements. The PIC produces a signal with frequency according to the distance, and activates a buzzer that alerts the user.

Specification המעבדה למערכות ספרתיות מהירות High speed digital systems laboratory Hardware The measurements calculations and the alert signal are produced by a microchip’s PIC18f452 microprocessor. Software The PIC18f452’s program was written using microchip’s development environment in C language. 4

System Block Diagram המעבדה למערכות ספרתיות מהירות High speed digital systems laboratory 5 US.R US.T IR sensor BUZZER PIC US.T Signal detecting circuits 40kHZ pulse transmitting circuit A/D