The skirt of this dress by Hong Kong artist Kathleen McDermott spreads out when someone comes too close to the wearer (+ slideshow).
As part of a collection of artworks called Urban Armour, McDermott designed the Personal Space dress that users can make themselves using simple electronics and umbrella parts.
"These pieces all use technology as way to react to the world around you, and they react in a way that is expressive," McDermott told Dezeen. "They are like extensions of the body in some way, exaggerating your own expression."
The designer used arduino boards, open-source electronics prototyping platforms, to read the sensor data. When the sensor detects an obstruction beyond the programmed threshold, the motors are turned on to open the dress.
The dress is made from a lace and polyester blend. The concertina-shaped structure that allows the dress to expand was cut from acrylic and bent with a heat gun. It uses 360 servo motors, an Arduino board and two ultrasonic sensors.
McDermott has uploaded tutorials for how to make this and other pieces in her Urban Armor collection to her website, in the hope that users will customise the open-source designs.
The collection also includes a scarf that responds to pollution data by moving to cover the wearer's face and Miss-My-Face, which turns on infrared LEDs to obscure the wearer's identity when it detects CCTV cameras.
"Right now wearable technologies focus on the virtual world but I am interested in how wearable technology can affect our daily, physical worlds," the designer explained.
"The dress is an artwork so there are not any consumers out there wearing it though I welcome others to try to make it," she added. "I think it's not immediately clear to many people that this is an artwork and not product."