3D stylus: Difference between revisions

A [[3D stylus]] (sometimes called a '''VR pen''' or '''spatial stylus''') is a pen-shaped input device that tracks motion in three-dimensional space, providing six degrees of freedom (3[[DOF]] position + 3DOF orientation). It enables precise pointing, drawing, and manipulation tasks that would be awkward with bulkier [[motion controllers]] or bare-hand tracking.<ref name="RoadToVR18"/>

[[File:MasslessPenVRStylus1.png|thumb|The **Massless Pen** 3D stylus used with a VR headset<ref name="RoadToVR18"/>]]

Unlike a traditional 2D stylus confined to a tablet surface, a 3D stylus operates freely in mid-air (or against any physical prop) and often incorporates buttons, a pressure-sensitive tip, and haptic (vibrotactile or force) feedback.<ref name="CreativeBloq21"/>  Some high-end models, such as the [[Massless Pen]], achieve sub-millimetre accuracy by fusing optical tracking with inertial measurement units (IMUs).<ref name="Tomshardware21"/>

3D styluses localise the pen in space via one or more of the following:

*'''[[Optical tracking]]''' – LEDs or retro-reflective markers observed by external [[camera]]s or [[headset camera]]s (e.g. [[Massless Pen]]).<ref name="RoadToVR18"/>

*'''[[Laser tracking]]''' – [[SteamVR]] base stations that sweep laser planes across photodiodes in the stylus (e.g. Logitech VR Ink).<ref name="RoadToVR19"/>

*'''[[Inside-out optical tracking]]''' – an on-board camera in the stylus (e.g. Wacom VR Pen) so no external trackers are needed.<ref name="RoadToVR20"/>

Many devices contain linear-resonant or rotary vibration motors that buzz when the virtual tip contacts a surface. Advanced desktop devices such as the 3D Systems '''Touch''' add 3DOF force feedback via motors in a gimbal.<ref name="3DSystemsTouch"/>

Most modern pens connect over Bluetooth LE or proprietary 2.4 GHz links, sending pose data at 60 – 240 Hz. Battery lives typically range from 2 to 6 hours of continuous use.<ref name="RoadToVR18"/>

*'''Professional CAD & Industrial Design''' – Wacom's [[Pro Pen 3D]] and [[VR Pen]] let engineers sketch surfaces in [[virtual reality]] while retaining tablet-style pressure sensitivity.<ref name="WacomCAD2019"/> Massless targets high-precision mechanical CAD workflows.<ref name="RoadToVR18"/>

*'''Medical imaging & surgical planning''' – Radiologists and surgeons annotate volumetric CT/MRI data in VR with a stylus. User studies show stylus + controller combinations outperform hand tracking for accurate marking tasks.<ref name="ApplSci23"/>

*'''Haptic simulation & training''' – 3D Systems [[Touch]] stylus provides force feedback for dental, orthopaedic, and robotic-surgery simulators.<ref name="3DSystemsTouch"/>

*'''Gaming & VR art''' – Creative professionals prefer pen-like tools such as [[Logitech VR Ink]] or [[Meta]]'s [[MX Ink]] for apps like [[Tilt Brush]], [[Quill]], or [[Gravity Sketch]].<ref name="CreativeBloq21"/>

*'''Education & visualization''' – The [[HP Zvr stereoscopic display]] (2015) shipped with a tracked stylus so students could “grab” and rotate holographic organs or molecules.<ref name="TheVerge2015"/>

Within fully immersive [[virtual reality]] and [[augmented reality]] (AR) [[head-mounted display]]s, a stylus offers a tangible “pen tip” that affords millimetre-scale accuracy. User studies comparing interaction modalities found that a stylus was the most precise for annotation, whereas hand tracking was the least. Pairing a stylus (for pointing) with a traditional controller (for grabbing) yielded the best overall performance.<ref name="ApplSci23"/> In AR, a stylus can be used to draw directly onto holographic content, e.g. labelling anatomical structures, which mitigates occlusion problems inherent in finger gestures.

==Notable devices and manufacturers =

* '''[[Wacom VR Pen]]''' (2020) – pressure-sensitive tip, thumb wheel, and inside-out optical tracking independent of base stations.<ref name="RoadToVR20"/>

* '''[[Logitech VR Ink Pilot Edition]''' (2019) and '''[[MX Ink]]''' (2023) – [[SteamVR]]-tracked and [[Quest]]-tracked styluses oriented toward design and VR art.<ref name="RoadToVR19"/>

[[File:LogitechVRInkPilotEdition1.png|thumb|The **Logitech VR Ink Pilot** stylus next to a Vive controller<ref name="RoadToVR19"/>]]

* '''Massless Pen''' (2021) – high-accuracy stereo-tracked wireless stylus aimed at professional [[CAD]].<ref name="RoadToVR18"/>

* '''HP Zvr stylus''' – tethered IR-tracked pen packaged with the [[HP Zvr stereoscopic display]] for engineering & education markets.<ref name="TheVerge2015"/>

==Historical development==

[[SensAble]]'s [[Phantom]] series (mid-1990s) were among the first commercial 3D styluses with force feedback, later re-branded by [[3D Systems]]. Interest waned during the 2000s consumer-VR drought, but the resurgence of headsets after 2014 spurred renewed development: HP Zvr (2015) demonstrated an early commercial “VR pen,” Logitech and Wacom launched tracked styluses from 2019 – 2020, and startups like Massless pushed accuracy to sub-millimetre levels.<ref name="RoadToVR18"/>

| [[data gloves]] || Fabric glove with [[IMU]]s/flex sensors || Rich gesture capture

While [[controllers]] and [[gloves]] excel at gross-motor tasks or gesture recognition, the fine-motor dexterity of a stylus remains unmatched for tasks such as sketching, spline editing, and point selection.<ref name="ApplSci23"/>

==References==

<references>

<ref name="WacomCAD2019">E. Garcia, “How Wacom enhances product design and CAD,” *Wacom Community* (5 Feb 2019). https://community.wacom.com/en-us/how-wacom-enhances-product-design-and-cad/</ref>

</references>

 

[[Category:Technical Terms]]

[[Category:VR Accessories]]

[[Category:Input Devices]]