The use of vibrations is, up to date, the easiest and the most common method used to provide tactile information. Actuators that can provide vibrotactile stimuli are nowadays included in many devices of common use, such as games controllers  and mobile phones. These devices use vibrations in order to provide silent alerts or haptic feedback. Furthermore, there are research labs that are using vibrotactile signals in order to provide directional information. Few examples of these interfaces are the following:
• Remote Guidance System - This device developed by the Sirslab at the University of Siena  is a wearable remote guidance system, which helps visually-impaired people during the navigation in unknown environments by providing vibrotac- tile directional information. The user wears camera glasses and two vibrotactile bracelets. A remote operator is connected with the system and receives the video
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A. Mansutti et al., Tactile Display for Virtual 3D Shape Rendering, PoliMI SpringerBriefs, DOI 10.1007/978-3-319-48986-5_2
captured by the camera glasses, and communicates the directional cueing by means of the vibrotactile stimulations provided through the bracelets.
- • University of Tokyo wearable system - This device  provides information related to the collisions of robotic arms during teleoperation and to support the operator with useful information, such as material stiffness and object shape.
- • Korea Institute of Science and Technology device - This interface  is an handheld input device, which uses vibrotactile cues to communicate spatial and directional information to a user who controls a manipulator arm. It consists in a six degrees of freedom (DOF) sphere-shaped handle. The surface of the sphere is divided into several sectors that vibrate in order to provide the information needed for controlling mobile robot with vibrotactile feedback.
- • TeslaTouch - The spread of touch screens in most common consumer mobile products, such as smartphones and tablets, has required the study of new technologies providing vibrotactile information. An example is the TeslaTouch  developed by Disney Research. This device is based on the electrovibration principle and does not use any moving parts. It is able to provide a wide range of tactile feedback feelings to fingers moving across a touch surface.
- • KAIST Surface Display - The researchers of the Korea Advanced Institute of Science and Technology have developed a new surface tactile display that can provide electrovibration and mechanical vibration simultaneously . The system has been equipped with a PDMS layer between two parallel plates, which allow obtaining a uniform vibrotactile feedback. In this interface the vibration is transmitted to the fingertip directly on the entire surface with large range of frequency.