Johannes Schöning

It is challenging to provide users with a haptic weight sensation of virtual objects in VR since current consumer VR controllers and software-based approaches such as pseudo- haptics cannot render appropriate haptic stimuli. To overcome these limitations, we developed a haptic VR controller named Triggermuscle that adjusts its trigger resistance according to the weight of a virtual object. Therefore, users need to adapt their index finger force to grab objects of different virtual weights. Dynamic and continuous adjustment is enabled by a spring mechanism inside the casing of an HTC Vive controller. In two user studies, we explored the effect on weight perception and found large differences between participants for sensing change in trigger resistance and thus for discriminating virtual weights. The variations were easily distinguished and associated with weight by some participants while others did not notice them at all. We discuss possible limitations, confounding factors, how to overcome them in future research and the pros and cons of this novel technology.

Browser extensions enrich users’ browsing experience, e.g., by blocking unwanted advertisements on websites. To perform these functions, users must grant certain permissions during the installation process. These permissions, however, give very limited information about the fact that they allow the extension to access user’s personal data and browsing behaviour, posing security and privacy risks. To understand users’ awareness of these privileges and the associated threats, we conducted an online survey with 353 participants, focusing on users’ attitude, knowledge, and preference towards extensions’ permission requests. We found that users report interest in seeking information, trust the developers but do little to protect their data. They have limited knowledge about the technical abilities of browser extensions and prefer per-mission statements that evoke a clear mental model. Based on our findings we derive recommendations for the improvement of browser extension permission dialogues through clear language, technical improvements and distinct responsibilities.