Ohmic-Touch: Extending Touch Interaction by Indirect Touch through Resistive Objects

When an object is interposed between a touch surface and a finger/touch pen, the change in impedance caused by the object can be measured by the driver software. This phenomenon has been used to develop new interaction techniques. Unlike previous works that focused on the capacitance component in impedance, Ohmic-Touch enhances touch input modality by sensing resistance. Using 3D printers or inkjet printers with conductive materials and off-the-shelf electronic components/sensors, resistance is easily and precisely controllable. We implement mechanisms on touch surfaces based on the electrical resistance of the object: for example, to sense the touching position on an interposed object, to identify each object, and to sense light, force, or temperature by using resistors and sensors. Additionally, we conduct experimental studies that demonstrate that our technology has a recognition accuracy of the resistance value of 97%.