Simulating the interactions that occur between a deformable tool and three dimensional objects is important for many training applications with haptic feedback. The physical properties of the tool, such as the flexibility, are particularly important for a variety of applications. In dentistry a successful root canal procedure could not be simulated without the flexibility of the tool being modelled. Simulating deformable tools with haptic feedback forms the main goal of the research.

A rod-like tool object has been simulated where a novel collision detection procedure has been developed to compute the contact points between the tool object and the virtual environment. The deformations of the tool have been modelled using the Finite Element Method. Both of these techniques are integrated into a new haptic rendering algorithm to compute the interaction forces between a three dimensional deformable virtual tool and a virtual object.

The remainder of this page contains background information about this research. For more details please consult one of the research team listed at the bottom of this page. This research was selected to appear at the Royal Society's Science Exhibition on 4th - 7th July 2005.

Background

Computer Graphics technologies have developed considerably over the past decades. Realistic virtual environments can be produced utilising improved techniques for rendering complex geometry coupled with per pixel effects. To enhance these environments the human's sense of touch, or haptic system, can be exploited to strive for an immersive experience. To achieve this haptic feedback devices, capable of exerting forces on the user, are incorporated.

Pictured to the left our two haptic devices used in our research, the Phantom Desktop (far left) and the Phantom Omni. Both the devices are produced by SensAble Technologies, and are capable of 6 degrees of freedom input and 3 degrees of freedom output.

The process of determining a reaction force for a given position of the haptic device is known as Haptic Rendering. For the past decade users have been able to utilise a haptic device to interact with a virtual environment, effectively probing with the tip of one finger. This type of single point haptic rendering is not particularly natural.

See how the haptic device can manipulate an object in three dimensional space. A single point algorithm is used to compute the forces between the virtual representation of the device and the model.

Download

Use the link below to download a Powerpoint presentation which provides an introduction to haptic feedback and its applications.

References

  1. DemoPresentation (4.3MB) Click to save the Zip file containing the Powerpoint presentation and movies.
  2. Madera, F.A., Day, A. M., Laycock, S. D., Fast Hierarchical Methods to Detect Collisions between Deformable Objects: A Comparison, Proceedings of Eurographics 2007, Prague.
  3. Laycock, S.D. and Day, A.M., A Survey of Haptic Rendering Techniques, Computer Graphics Forum, 26(1), March 2007, pp. 50-65
  4. Laycock, R.G., Laycock, S.D. and Day, A.M., Haptic Navigation and Exploration of High Quality Pre-rendered Environments, 7th VAST06, Cyprus, 2006, pp 17 - 24. ISBN 3-905673-42-8 
  5. Madera, F.A., Day, A. M., Laycock, S. D., Collision Detection for Deformable Objects Using Octrees, Proceedings of Theory and Practice of Computer Graphics Conference EGUK, 2006.
  6. Laycock, S.D. and Day, A.M., Incorporating Haptic Feedback for the Simulation of a Deformable Tool in a Rigid Scene, Computers & Graphics, 29(3), 2005, pp. 341-351
  7. Laycock, S.D. and Day, A.M., A Hybrid Collision Detection Approach for the Haptic Rendering of Tools, In Proceedings of Computer Graphics International (CGI), Crete, 2004, pp. 148-155.
  8. Laycock, S.D. and Day, A.M., Simulating Deformable Tools with Haptic Feedback in a Virtual Environment, WSCG, Plzen, 2003, pp. 75-81.
  9. Laycock, S.D. and Day, A.M., Recent Developments and Applications of Haptic Devices, Computer Graphics Forum, 22(2), 2003, pp. 117-132.
  10. Laycock, S.D. and Day, A.M., The Haptic Rendering of Polygonal Models involving Deformable Tools, EUROHAPTICS 2003, Dublin, 2003, pp. 176-192. 
     

Exhibitions and Demonstrations

Our haptics research has been demonstrated at the following events.

  • Game On at the UEA Sportspark, 4th September 2006.
  • Spring Fling at the Norfolk Showground, 11th April 2006.
  • Royal Society's Summer Science Exhibition, 4-7th July 2005.
  • Norfolk Show, 29th-30th June 2005.

Research Team