Hi again! Here is the new design for "Envision The Future Design Challenge" In this case I have design a proximity sensor to blind people.  Also it's a funny ghost  similar to Pacman's ghost. In this case we will need to add electronic devices, as ultrasonic sensor and "arduino nano" all the material costs around 30€ . The sensor detect the distance between us and one object (for example the wall). and with the help of a buzzer, we will hear tones, with a proportional frequency to the distance, to closer the frequency is faster. Features: - It's useful to detect objects, it could be used daily to help to blind people, or as methodology to learn the distance for example of your steps. - It has 2 supports on the back, it's useful to support the device for example in your belt. - it could be configured as you want, changing distance, frequency, or the tone.. - the case for the battery, is available for Button batteries or 4xAAA battery (I recomend to use at least 500mA; and 5V). Construction: - Do you need wires, arduino nano, buzzer, HC SRO4 sensor, optionally you can use a switch, to switch off/on. -first insert the program to the arduino nano, it exist huge amount of videos in youtube explaining the code, I add the code that I have used. - After plug all the devices. (the buzzer will be the last). * I attach an squematic. - Insert all the components in the case of the phantom. first, the HCSR04 sensor, after the battery and the switch, and finally the  arduino and buzzer. I hope this new device will be useful for you!! Thank you for your attention! -------