This project is designed to guide a visually impaired person to walk and avoid bumping into obstacles. Low cost ultrasonic rangefinders along with a microcontroller is used to measure the distance to obstacles and if they are close enough provide a feedback to the user in form of beeps or vibrations.
The project is made on a small single layer PCB. The sensors are not mounted on the PCB but they are mounted on front of the stick and connected to the main board using wires. All the parts of project PCB is shown in the image below.
Using the stick is simple, just plug the power bank to the USB plug (refer the image above) and switch on board using the On/Off Switch. The power indicator LED should glow. The system is now ready.
For testing purpose keep all the three sensors on flat surface such as ultrasonic beam emitted by them is horizontal. Make sure their are no obstacles in front of any sensor up-to a distance of 1 meter. Slowly come close to the center sensor until the buzzer starts beeping. For obstacles found by the center sensor their are two quick beeps. Try to remember this beep patten. Now move slowly towards the right sensor also make sure their is no obstacle in front of the front sensor. For obstacles sensed by right sensor it will give three quick beeps. Similarly for left sensor it will give single beep.
These beep patterns are easily recognizable after few days of usage.
While testing left or right sensor make sure the front sensor is free of obstacle, because front (center) sensor has highest priority, if it has obstacles in front of it, buzzer will give two quick beeps indicating obstacle in center.
We cordially thanks the following peoples who shared this page on various social networks and insprided us to develop more quality contents!
Ahmed Badawy, Shivam, Sathish, Della, Tharindu Gunarathne, Taye Khan, Shahulhameed, Shahul Hameed, , Avinash Gupta,