WAVI: improving motion capture calibration using haptic and visual feedback

Motion tracking systems are gaining popularity and have a number of applications in research, entertainment, and arts. These systems must be calibrated before use. This process requires extensive user effort to determine a 3D coordinate system with acceptable accuracy. Usually, this is achieved by rapidly manipulating a calibration device (e.g. a calibration wand) in a volume for a set amount of time. While this is a complex spatial input task, improving the user experience of calibration inspired little research. This paper presents the design, implementation, and evaluation of WAVI --- a prototype device mounted on a calibration wand to jointly provide visual and tactile feedback during the calibration process. We conducted a user study that showed that the device significantly increases calibration quality without increasing user effort. Based on our experiences with WAVI, we present new insights for improving motion tracking calibration and complex spatial input.