In the field of virtual reality, engineers and software developers aspire to find new ways that will increase the realism and maximize the immersion of a users experience to the fullest. They seek to break the boundaries of technologies that allow a user to touch, grasp, and manipulate virtual objects to the point that the person really feels the same way as when they are handling the objects in the real world. Recently, a new glove has been designed by Researchers at the École Polytechnique Fédérale de Lausanne (EPFL) and Eidgenössische Technische Hochschule (ETH) in Zürich that enables its user to feel and manipulate virtual objects with extreme accuracy to reality.
This VR glove they are calling “DextrES” is only 2 millimeters thick, ultra-lightweight (weighing at less than 8 grams per finger), and will be able to run off a small battery (requiring only 200v and a few milliwatts of power to run). All these facts combined are accountable for the glove having unparalleled freedom of movement. Furthermore, its system provides extremely realistic haptic feedback, and study trials with volunteers have proven all this to be true. What makes such weightlessness and low power requirements possible is the fact that the glove does not create a movement, but blocks one.
“The human sensory system is highly developed and highly complex,” says Otmar Hilliges, head of the Advanced Interactive Technologies Lab at ETH Zürich. “We have many different kinds of receptors at a very high density in the joints of our fingers and embedded in the skin. As a result, rendering realistic feedback when interacting with virtual objects is a very demanding problem and is currently unsolved. Our work goes one step in this direction, focusing particularly on kinesthetic feedback.”
The approach for how it works is based on an electrostatic clutch generating up to 40 Newtons of holding force on each finger (~2 kilos). The holding force is achieved by modulating the electrostatic attraction between flexible elastic metal strips to generate an electrically controlled friction force. In other words, the metal strips are separated by a thin insulator that reacts whenever contact is made with a virtual object. The reaction is an onboard controller applying a voltage shock to the metal strips causing them to stick together. When the reaction happens it creates a breaking force blocking the movement of the user’s fingers and by doing so signaling to the mind that a virtual object is being held. When the user let’s go of the virtual object, the voltage is switched off and the user regains full movement of their fingers. The variety of grasp types applicable include, lateral, precision, power, and parallel grasps.
The development of “DextrES” is a joint research project; the hardware by EPFL at its Microcity campus in Neuchâtel, and the virtual reality system by ETH Zürich (whom also carried out the user tests). “Our partnership with the EPFL lab is a very good match. It allows us to tackle some of the longstanding challenges in virtual reality at a pace and depth that would otherwise not be possible,” adds Hilliges. Their glove will be presented at the upcoming ACM Symposium on User Interface Software and Technology (UIST).
“Gamers are currently the biggest market, but there are many other potential applications — especially in healthcare, such as for training surgeons. The technology could also be applied in augmented reality,” says Shea.
The next phase of their project sees the scaling up of the device and system by applying it to other parts of the body. They intend to use conductive fabric in order to achieve this. The team is planning on creating a full VR suit with similar technology.
