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During this project, a mobile haptic feedback device, aimed at virtal object representation in virtual reality was developed. The device is capable of providing its users with passive force feedback between their thumb and index finger. The device consists of a magnetorheological fluid damper, suspended between the thumb and the index finger by means of a novel mounting mechanism. In the dampers OFF state, the user’ s movements can contract and extend this damper with relative ease. In the dampers ON state, an electromagnetic coil in the piston of the damper is activated, creating a magnetic field over the fluid in the damper This couses the affected fluid to solidify, significantly increasesing the damper’s resistance. The user’s fingers will sense this increase in resistance when they try to move them towards one another. In the right setting, this increase in resistance between the fingers may be experienced by the user as virtual object contact. By varying the intensity of the magnetic field over the dampers fluid, the damper is able to represent both rigid or ductile objects. The purpose of providing this type of feedback is twofold. It may allow people to experience virtual object contact, as they would in the real world. Previous research has indicated this type of haptic feedback could improve accuracy during virtual object grasping. The presence of this type of feedback may also enable people to disinguish the compliance of different virtual objects. A practical prototype evaluation was held to verify wheter or not the developed device was capable of providing the haptic sensations described above. In this evaluation, participants were asked to determine virtual object contact and to judge virtual object compliance. Due to the large internal resistance of the prototype, the difference between contact and no contact could not be determined for very ductile “objects”. Rigid object contact was detected far more easily. Participants were more adapt at sensing differences between different damper compliance values. The developed device was the result of a study into the field of haptic feedback. At the start of this study, the limitations of current haptic feedback devices were mapped. Simultaneously, a number of smart materials was studied to determine whether the application of one or more of these materials in a haptic feedback device could aid in overcoming some of the limitations found in existing devices. Out of the opportunities found, the creation of an in hand force feedback device aimed at simulating object contact was deemed most interesting. To provide the force feedback needed for this application, the descision was made to use magnetorheological fluid in a linear damper configuration. This choice was made based on the succesfull application of magnetorheological fluid in other haptic feedback devices, on the potentially high power density of magnetorheological dampers and on the relative simplicity of such a damper. Prior to the device’s development, the field of haptic feedback was studied. The purpose of this study with the purpose of identifying opportunities which are currently not or insufficiently fullfilled by existing haptic feedback devices. which could be fulfilled by the application of one or more smart material To come to the final design, a series of sketches was made, detailling potential methods to provide force feedback using a magnetorheological damper. Simultaneously, a calculation model was made and evaluated to determine the optimum geometry for a magnetorheological damper. At the end of this process, an optimised damper geometry was combined with a feasible method of mounting the damper to the hand, forming the final product.