This is a prototype of an ordinary dustbin made smarter and personified with interesting cartoon-like characteristics such as the eye movements, recorded perky speech, falling whistle sound effects.Background/The why..
A clean environment is essential for healthy living. Keeping the environment clean has always been a passion. Why we took up the project is because we realized that people still litter up the streets ignorantly even with dustbins around. Therefore we decided to take a normal ordinary dustbin and transform it to one that would be irresistible to ignore so as to encourage passers-by to avoid littering their surroundings.Overview of how it works
We've used two types of sensors; the ultrasonic sensors and the PIR motion sensors each strategically positioned on the dustbin. For the ultrasonic sensors, we got three on the outside - 2 on the sides and 1 at the centre as shown in the pictures. PIR motion sensors are two - one on the inside and the other outside right at the center. The outer PIR is used in conjunction with the ultrasonic sensors to determine whether a person is approaching the dustbin, leaving or just passing by so as to play the recorded audio files of speech. The inner PIR motion sensor detects when something has been dropped into the dustbin then plays the audio files for a falling whistle sound cartoon effects.
The microSd card slot is used to store the audio files which are in 4 categories; a passing by category, approaching category, leaving, and throwing something into the dustbin category. There are multiple audio files in each category. The 101 selects any audio files from within the category that it is supposed to select from. It selects randomly using the arduino function random. The audio files are taken from the microSD card module via the SPI interface, processed using pwm inorder to output an audio signal through the 3.5mm audio jack, which is plugged into a 3.5mm trrs capable amplifier. The amplifier is battery powered or can also be charged by the power supply being passed to the arduino 101. The arduino 101 is actually powered externally. Its the one that processes all the audio using pwm with no external DAC (Digital to analog converter).
The micro servos bring about the synchronous movement of the eyes; up, down, side to side. And the eyes will tend to "look" towards the side that the ultrasonic sensor detects someone approaching. e.g when a person approaches the dustbin towards the left, the eyes will turn left to give the impression that it sees you coming towards it. The random eye movements is as a cause of the pwm generated for audio but we decided not to fix it because it tends to attract attention when the dustbin is "talking" which is what we want.