The boundaries between the digital and physical world around us are fading. Traditionally passive objects like mirrors, windows, coffee tables, clothes and even plants are now becoming interactive. One of the innovations in this area is Luminous Carpets. It is a carpet with embedded LED lights. The product is a collaboration between Philips and Dutch carpet maker Desso.

Making it interactive

Although the carpet itself does not contain sensors to detect who is standing where, it is possible to add external sensors to detect the presence of people. I was invited by Luminous Carpets to setup an experiment to see if their demo floor could become interactive by adding a Kinect sensor. Here’s a video that shows some of the results of the singe day trial.

The Kinect was positioned at the front of the floor at a relatively large distance (> 3 meters) to be able to see all of the floor area. After setting up the equipment a calibration had to be applied for lining up the Kinect coordinate frame with the coordinate frame of the Luminous Carpet demo floor. The demo application was a WPF based application that generated a small grayscale image in the top left corner of the screen with a size of 112 x 56 pixels. The floor controller could then use this as a HDMI input for controlling the pixels of the luminous carpet.

By using Kinect in a frontal view body tracking can be used to build interactivity that understands joint positions. Individual joints can be projected to the floor taking into account their height above the floor. This can for instance be used to give the user a feeling that he is holding a lantern that lights up the floor. This positioning of the Kinect also implies looking into the direction of the sensor for best tracking results. For interaction with a floor however there is no direct directional preference for interaction other than suggested by the walls surrounding it.

Using the Kinect in a frontal setup may also cause that multiple users can occlude each other. Typically this is prevented by using a sensor that looks down from a large height and using blob detection and tracking for building the interactivity.

Natural surface interactions

Blending the digital and the real world can go beyond using hand-held devices like iPad or head-mounted devices like HoloLens. Any surface that surrounds us in our everyday lives can be made interactive by combining sensors and visual, tactile or auditive feedback. The surfaces that have the highest potential for natural interaction are those that we are already used to interact with on a daily basis. And if we don’t have to equip ourselves with wearables it can feel even more natural.