Providing force and vibrotactile feedback with haptic devices for simulating industrial tools in immersive Virtual Reality

Virtual reality is an emerging technology that in recent years has become more present in everyday life of the people due to cost reduction of the hardware and the increased quality of the simulation. The goal of this technology is the creation of a synthetic environment that is as realistic as possible and could be used both for the entertainment domain and for the industrial domains, like for example aerospace and automotive, in order to perform, eg., training in a safe environment. Considering the importance of providing users with realistic physical stimuli and the current limitations of technology, the objective of this thesis work was to compare two different systems that are able to provide haptic sensations. Starting from a real screwing experience in two different materials (wood and aluminium) the vibration signals provided by an electrical screwdriver are captured by using an accelerometer and then, after a Fourier analysis, the sinusoids are retrieved. Those signals are then rendered into different haptic systems: the first one is composed by ManusVR gloves, used for finger and hand tracking, and by a 3D printed mockup, obtained by a laser scan of the real electric screwdriver, which is used as holder for an HTC Vive controller; the second system is composed by SenseGlove Development Kit One (FFB), a pair of gloves that are able to provide both vibrotactile and force feedback on every finger. In order to use the two systems, it is created a virtual reality experience where the user is immersed in a virtual workshop and, after a short tutorial that is helpful for understanding how to interact with objects, he/she has to move several gussets in the correct position; afterwards he/she has to screw three screws with different lengths in the wood and repeat the same operation in the aluminium. At the end of the virtual reality experience the users are asked to fill some questionnaires (VR-USE, SUS, SIM-TLX, EQ and a custom one for haptic purpose for benchmarking the systems) in order to evaluate the usability of the application, the realism of the experience, the physical and mental workload and to compare the two different systems. The results indicate that both systems are usable, but the one including the mockup offers a better passive haptic feedback due to its shape and could be worn in an easy way, whereas SenseGlove provides a higher fidelity haptic feedback.