Usability evaluation of the EPOCH multimodal user interface: Designing 3D tangible interactions

This paper expands on the presentation of a methodology that provides a technology-enhanced exhibition of a cultural artefact through the use of a safe hybrid 2D/3D multimodal interface. Such tangible interactions are based on the integration of a 3DOF orientation tracker and information sensors with a 'Kromstaf' rapid prototype replica to provide tactile feedback. The multimodal interface allows the user to manipulate the object via physical gestures which, during evaluation, establish a profound level of virtual object presence and user satisfaction. If a user cannot manipulate the virtual object effectively many application specific tasks cannot be performed. This paper assesses the usability of the multimodal interface by comparing it with two input devices--the Magellan SpaceMouse, and a 'black box', which contains the same electronics as the multimodal interface but without the tactile feedback offered by the 'Kromstaf' replica. A complete human-centred usability evaluation was conducted utilizing task based measures in the form of memory recall investigations after exposure to the interface in conjunction with perceived presence and user satisfaction assessments. Fifty-four participants across three conditions (Kromstaf, space mouse and black box) took part in the evaluation.