# Immersive Virtual Reality Experience of Historical Events Using Haptics and Locomotion Simulation
## 1 Introduction
### Related Work  
Virtual reality for cultural heritage offers a possible solution to allow visiting inaccessible sites. There are works regarding such immersive environments in which users cannavigate in the virtual environment, interact with 3D objects, and be informed using gestural interaction [4]. Multimodal interfaces are essential for creating the necessary sense of presence, that these applications require [5]. Many workflows use a Head-Mounted Display (HMD) device to visualize the data acquired, including the necessary programming for navigation and interactions [6; 7; 8]. Communicating knowledge regarding cultural heritage with the help of a serious game is another well-established concept and such examples can be found in [9; 10; 11]. Another important challenge is accessing the underwater cultural wealth. Recent research has focused on the use of Augmented Reality (AR) by divers using cellphones and hybrid markers [12], as well as Virtual Reality (VR) applications for users to explore underwater monuments [13].  
Locomotion in VR has been a considerable challenge in the research field for the last few years. Studies show that the most natural experience is when the users are able to physically walk in the real world [14]. Locomotion techniques are mainly split into two categories. The first one includes the techniques that allow the user to move in a way that is not feasible in the real world, using hand-based manipulation either with controllers [15] or without [16; 17]. The second category is about the techniques that enable the physical movement of the user, walking, running, and so forth, and can be vehicle- or body-centric [18]. Body-centric approaches are based on repositioning, through a device that constrains them in a fixed position, proxy gestures, and redirected walking [19]. Repositioning can be achieved with active components, like motorized platforms and floor tiles, or utilize passive components like low-friction omnidirectional treadmills or slippery shoes-based interfaces able to decrease the friction produced by the users' steps. These passive systems offer a simpler and less expensive solution, and are often used for rehabilitation purposes [20; 21].  
Today, VR technologies are used in a wide range of applications, simulating the real world dynamically and responding in real-time to the users. Integration of haptic feedback in VR is widely accepted as a means to augment the VR experience [22]. By adding force/tactile sensation, the users are expected to be able to perform more complex tasks while being physically aware of the objects they are manipulating [23]. Tactile feedback devices provide input to the user's skin. They try to recreate the feeling of a shape, a texture, sometimes even the thermal properties of a virtual object. Kinesthetic feedback devices apply forces on the user's skeleton to create the impression of movement and/or resistance [24]. In real life, when touching an object a person gets both these types of feedback. The goal for haptic devices is to allow the user to feel virtual object features such as folds, textures, edges, temperature, and slipperiness. Together with sight and hearing, utilizing the sense of touch enriches the immersion of the user. A haptic device can also enhance a learning experience not only on an elementary [25] but also on a professional level [26].