Cookies Policy
X

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here

Full Access Changes in haptic sensitivity during tool use: Implications for optimal design of visual-haptic devices

No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Changes in haptic sensitivity during tool use: Implications for optimal design of visual-haptic devices

  • PDF
  • HTML
Add to Favorites
You must be logged in to use this functionality

image of Seeing and Perceiving
For more content, see Multisensory Research and Spatial Vision.

Optimising haptic sensitivity in visual-haptic interfaces can have important benefits, particularly in situations where visual information is relatively unreliable (for example in surgical devices, where there is often a lack of normal visual depth cues). Many haptic devices alter the normal relationship between object size and hand opening, and so might be expected to alter haptic sensitivity. To determine how to optimise haptic sensitivity in such situations, we measured haptic size sensitivity as a function of object size (i) during normal grasping, and (ii) using pliers-like tools that changed the gain between hand opening and object size. Haptic stimuli were created using force-feedback robots, and we measured discrimination thresholds using a two-interval forced-choice task. We first showed that when participants directly grasped objects with their hands haptic size sensitivity did not follow Weber’s law, but instead varied non-monotonically with object size/hand opening; thresholds were lowest for object sizes around 45 mm and increased non-linearly for larger and smaller objects. Second, when using the pliers, sensitivity in units of hand opening was unchanged from normal grasping. Thus, thresholds in units of object size were simply the product of the non-monotonic haptic size sensitivity function, above, and the tool gain. Taken together, these results show that there is a unique tool gain that maximises haptic sensitivity to each object size. Our results show how the ‘tool gain’ of haptic devices should be altered to optimise sensitivity to the range of object sizes in a particular scene.

Affiliations: 1: School of Psychology, Bangor University, GB

Optimising haptic sensitivity in visual-haptic interfaces can have important benefits, particularly in situations where visual information is relatively unreliable (for example in surgical devices, where there is often a lack of normal visual depth cues). Many haptic devices alter the normal relationship between object size and hand opening, and so might be expected to alter haptic sensitivity. To determine how to optimise haptic sensitivity in such situations, we measured haptic size sensitivity as a function of object size (i) during normal grasping, and (ii) using pliers-like tools that changed the gain between hand opening and object size. Haptic stimuli were created using force-feedback robots, and we measured discrimination thresholds using a two-interval forced-choice task. We first showed that when participants directly grasped objects with their hands haptic size sensitivity did not follow Weber’s law, but instead varied non-monotonically with object size/hand opening; thresholds were lowest for object sizes around 45 mm and increased non-linearly for larger and smaller objects. Second, when using the pliers, sensitivity in units of hand opening was unchanged from normal grasping. Thus, thresholds in units of object size were simply the product of the non-monotonic haptic size sensitivity function, above, and the tool gain. Taken together, these results show that there is a unique tool gain that maximises haptic sensitivity to each object size. Our results show how the ‘tool gain’ of haptic devices should be altered to optimise sensitivity to the range of object sizes in a particular scene.

Loading

Full text loading...

/deliver/18784763/25/0/18784763_025_00_S138_text.html?itemId=/content/journals/10.1163/187847612x647793&mimeType=html&fmt=ahah
/content/journals/10.1163/187847612x647793
Loading

Data & Media loading...

http://brill.metastore.ingenta.com/content/journals/10.1163/187847612x647793
Loading
Loading

Article metrics loading...

/content/journals/10.1163/187847612x647793
2012-01-01
2017-02-23

Sign-in

Can't access your account?
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation