Exploring the effects of replicating shape, weight and recoil effects on VR shooting controllers

Commercial Virtual Reality (VR) controllers with realistic force feedback are becoming available, to increase the realism and immersion of first-person shooting (FPS) games in VR. These controllers attempt to mimic not only the shape and weight of real guns but also their recoil effects (linear force feedback parallel to the barrel, when the gun is shot). As these controllers become more popular and affordable, this paper investigates the actual effects that these properties (shape, weight, and especially directional force feedback) have on performance for general VR users (e.g. users with no marksmanship experience), drawing conclusions for both consumers and device manufacturers. We created a prototype replicating the properties exploited by commercial VR controllers (i.e. shape, weight and adjustable force feedback) and used it to assess the effect of these parameters in user performance, across a series of user studies. We first analysed the benefits on user performance of adding weight and shape vs a conventional controller (e.g. Vive controller). We then explore the implications of adding linear force feedback (LFF), as well as replicating the shape and weight. Our studies show negligible effects on the immediate shooting performance with some improvements in subjective appreciation, which are already present with low levels of LFF. While higher levels of LFF do not increase subjective appreciations any further, they lead users to reach their maximum distance skillset more quickly. This indicates that while adding low levels of LFF can be enough to influence user’s immersion/engagement for gaming contexts, controllers with higher levels of LFF might be better suited for training environments and/or when dealing with particularly demanding aiming tasks

Psychometric properties of the Spanish version of the Jefferson Scale of Empathy: making sense of the total score through a second order confirmatory factor analysis

Background: Empathy is a key aspect of the physician-patient interactions. The Jefferson Scale of Empathy (JSE) is one of the most used empathy measures of medical students. The development of cross-cultural empathy studies depends on valid and reliable translations of the JSE. This study sought to: (1) adapt and assess the psychometric properties in Spanish students of the Spanish JSE validated in Mexican students; (2) test a second order latent factor model. Methods: The Spanish JSE was adapted from the Spanish JSE-S, resulting in a final version of the measure. A non-probabilistic sample of 1104 medical students of two Spanish medical schools completed a socio-demographic and the Spanish JSE-S. Descriptive statistics, along with a confirmatory factor analysis, the average variance extracted (AVE), Cronbach's alphas and composite reliability (CR) coefficients were computed. An independent samples t-test was performed to access sex differences. Results: The Spanish JSE-S demonstrated acceptable to good sensitivity (individual items - except for item 2 - and JSE-S total score: -2.72 < Sk < 0.35 and -0.77 < Ku < 7.85), convergent validity (AVE: between 0.28 and 0.45) and reliability (Cronbach's alphas: between 0.62 and 0.78; CR: between 0.62 and 0.87). The confirmatory factor analysis supported the three-factor solution and the second order latent factor model. Conclusions: The findings provide support for the sensitivity, construct validity and reliability of the adapted Spanish JSE-S with Spanish medical students. Data confirm the hypothesized second order latent factor model. This version may be useful in future research examining empathy in Spanish medical students, as well as in cross-cultural studies.info:eu-repo/semantics/publishedVersio

Characterization of ferromagnetic contacts to carbon nanotubes

We present an investigation of different thin-film evaporated ferromagnetic materials for their suitability as electrodes in individual single-wall and multi-wall carbon nanotube-based spin devices. Various electrode shapes made from permalloy (Ni81Fe19), the diluted ferromagnet PdFe, and PdFe/Fe bilayers are studied for both their micromagnetic properties and their contact formation to carbon nanotubes. Suitable devices are tested in low-temperature electron transport measurements, displaying the typical tunneling magnetoresistance of carbon nanotube pseudo-spin valves

Eintwicklung eines Kraft-Feedback-Systems für virtuelle Umgebungen

The development of a force feedback system for virtual assembly simulation was motivated by the lack of haptic feedback in these VR application domain allowing realistic interaction in real size with 6 degrees of freedom. The requirements for the system where analysed manly by the industrial partners DaimlerChrysler, BMW and VW. Based on them we developed hardware and software concepts and implemented them during the project "Development of a Force Feedback System for Virtual Environments", which was part of the integrated project iViP (integrated Virtual Product Creation) funded by the German Federal Ministry of Education and Research. The research partner DLR developed a 7 degrees of freedom lightweight robot with advanced control system suitable to use it as haptic device. The haptic rendering simulation was developed at IGD, based on a hybrid voxel and surface point representation of the scene, and integrated to a VR system. Usability tests with users from the industrial partners had positive results and guided the direction for further development

Assembly Verification in Digital Mock-Ups using Force Feedback

Virtual product creation will play a key role in industrial product development in the future. Creating a virtual prototype needs a verification of a collision free final place of all parts and a collision free path to it, the assembly path. This paper addresses the second point of this issue, because nowadays CAD software do not solve it. The DLR lightweight robot is used as a force feedback device together with a digital 3D Mock-Up (DMU), such that the human designer can explore the parts and their assembly paths with his kinesthetic skills in a natural way. This allows a faster and more reliable virtual product creation process while saving costly hardware Mock-Ups. We depict the components of a Virtual Reality System and a 6 degrees of freedom haptic rendering algorithm integrated into it. The advanced hardware and control architecture of the DLR lightweight robot is presented with regard to the use as force feedback device in real size assembly simulation. User tests in a practical scenario gave good results for the system