Surgical Training Using Proxy Haptics; A Pilot Study

• Author / Creator

  Rahmani Hanzaki, Mahdi

• In recent years and with the advancement of technologies, the applications of Virtual Reality (VR) have been used in many fields. Technologies such as high-resolution digital displays, GPUs and CPUs, are now able to render complex virtual worlds in real-time. Modern VR systems can create high-quality VR environments that can be used in numerous applications such as entertainment, education, and medical training.

  VR has been used in surgical training to either replace more expensive training techniques (such as cadavers) or serve alongside additional training techniques to increase a surgeon's skills. As VR technologies evolve, one can trick the brain into thinking that a user is seeing and touching real-world objects. To trick the brain at a believable level, one needs to be able to generate feedback to multiple human senses (vision, haptic, sound) that are realistic and consistent with behaviors and sensations in the real world. Because of these requirements, many systems have been proposed to deal with the multi-sensory outputs VR needs to produce in order to be useful for real-world applications such as surgical training. Visual perception can be dealt with very well using modern Head-Mounted Displays (HMDs) and advanced rendering software.

  On the other hand, haptic perception is still at its infancy and has not reached the same level of realism that HMDs can provide. Many haptic systems use force-feedback devices to create a sense of touch, most of them require to hold a wand attached to a small robot or wear a glove that provides forces or friction to a user's hand movement. The problem with standard haptic devices is that they do not provide haptic feedback to all parts of the body hence reducing the sense of immersion and making their use impractical in complex simulations.

  This thesis propose a solution to the realism of haptic perception in VR by using the concept called “proxy haptics.” In proxy haptics, real physical props are placed around the real environment to match their virtual counterparts. If the physical props are co-registered with the virtual world, a compelling sense of tactile sensation can be achieved, for example, how a mannequin can be used to represent a virtual patient. If the mannequin is co-registered in 3D relative to the virtual user locations, one can be tricked to believe that they are touching a real patient. A prototype proxy haptic system was developed and a pilot study was performed to determine the effects of our system for simple surgical training tasks. The goal of this pilot study was to determine if people think our system is more believable than standard VR by asking them to do simple tasks such as moving the patient's hand or pointing a syringe to specific target locations. In the pilot project, we compared the results of using our system against a standard VR system with no haptic feedback (i.e., wand controller only). In the end, our results show that the amount of time the users need to complete the pointing tasks is longer in the system with proxy haptics than using the VR wand. This makes sense as in the virtual world objects are ghosts and one can move freely without collisions. In the proxy haptic world, objects are real and the laws of physics do apply. Our results also show that from a user perspective, our system is more believable and closer to the real world than the standard VR interface.

• Subjects / Keywords

  • HTC Vive
  • Haptic
  • Proxy Haptic
  • Surgery
  • Surgical Training
  • VR
  • Virtual Reality
  • HMD
  • Head Mounted Display

• Graduation date

  Spring 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-6047-hz13

• License

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