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Research draft

finger

vr.tr.finger · PHY.OBJ

Enable an AI agent to identify an individual finger, record its observable condition and functional capabilities, and determine which interactions are appropriate under known constraints.

Thing Registry Physical world and living systems

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

Researched by: Codex + Grok

Purpose and description

Enable an AI agent to identify an individual finger, record its observable condition and functional capabilities, and determine which interactions are appropriate under known constraints.

A finger is a distal, independently movable ray of the human (or primate) hand, comprising a metacarpal and a chain of phalanges with joints, tendons, vessels, and digital nerves, used for grasp, fine manipulation, and tactile sensing.

It can be Locate and label the finger and its visible parts within a hand observation.; Track local appearance, dimensions and reported symptoms across comparable observations.; Describe demonstrated bending, straightening and digit-specific movement.; Record the finger's contribution to pointing, touching, tapping, pinching or grasping.; Assess contact and fit requirements for a related glove, ring, sensor or support.; Gate proposed contact, movement or loading against consent, recorded restrictions and unresolved condition..

Distinguishing features

Establish that the digit belongs, or previously belonged, to a hand rather than a foot; appearance alone does not settle this.

Identify one digit within the hand rather than treating the palm or the entire hand as the finger.

Distinguish biological tissue from an artificial replacement, recording a prosthesis as a related component.

Distinguish the complete digit or remaining digit from a nail, fingertip fragment or other local part.

Record thumb versus non-thumb identity explicitly rather than inferring interchangeable structure or movement.

Scope

+ Finger identity, hand laterality, digit position and attachment status

+ Local segments, joints, fingertip, pad, skin and nail where present

+ Observed movement, sensation and contribution to hand tasks

+ Local condition, reported symptoms and changes over time

+ Finger-specific contact, loading and assistance constraints

- Whole-hand coordination and overall grip performance

- Arm and wrist anatomy or movement except as context for finger observations

- Person-level identity, health history and clinical diagnosis

- Toes and other foot structures

- Artificial fingers, prosthetic components and robotic grippers as independently modelled things

- Rings, gloves, tools and other objects contacting the finger

Characteristics

Digit identity
thumb | index | middle | ring | little | additional digit | indeterminate Locates the finger within the hand and prevents assumptions that all digits have the same structure or role.
Hand association
associated hand reference; left | right | indeterminate Disambiguates similarly named fingers and establishes the context for observations.
Attachment and extent
attachment: attached | partially attached | detached | unknown; extent described by observed landmarks Separates digit identity from its current physical continuity and remaining parts.
Finger dimensions
length and circumference in mm, with landmarks, posture and measurement method Supports fit assessment and comparison without treating differently measured dimensions as equivalent.
Joint movement
degrees by identified joint and movement direction, distinguishing active from passive assessment Describes demonstrated movement without collapsing all joints into one mobility score.
Local surface condition
observed skin, pad and nail condition, including location, time and visibility limitations Identifies contact surfaces and visible changes relevant to interaction.
Reported sensation and discomfort
person-reported location, sensation, severity scale if used, trigger and time; unknown when not assessed Keeps subjective experience distinct from what an image or movement observation can establish.
Demonstrated task contribution
task reference with finger role, contact location, assistance and observed outcome Connects the finger to actual use without attributing whole-hand performance to one digit.
Interaction restrictions
per-action restrictions with source, applicable conditions and review time Prevents an observed capability from being interpreted as permission to exercise it.

Also called

female fingerhuman fingermiddle fingerindex fingerring fingerlittle fingerright middle fingerleft middle fingerright index fingerleft index fingerright ring fingerleft ring fingerright little fingerleft little finger

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.finger-artifact

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 12 findings · 24 questions.

Digit identity and boundaries Establish which finger is modelled and what physical extent belongs to it.

Digit position, thumb identity and altered anatomy affect both recognition and interpretation of function.

Hand and digit location

Locate the individual digit within its associated hand.

Digit designation

Record the supported digit designation and hand association, preserving ambiguity.

  1. Which hand is this finger associated with, and what establishes laterality? provenance
  2. Is this the thumb, index, middle, ring, little or an additional digit, and is that designation uncertain? definition

Physical extent

Separate the individual finger from the hand, local fragments and replacements.

Attachment and part boundaries

Record attachment and remaining extent without assuming a complete or typical finger.

  1. What landmark defines this finger's proximal boundary with the hand for this model? boundary
  2. Which portions are present, absent, detached or replaced, and how was this established? provenance
  3. Which adjacent or attached structures require separate linked models? boundary
Finger structure and contact surfaces Describe the finger's segments, joints and surfaces at the detail supported by evidence.

Finger movement and contact depend on specific local structures rather than a generic object shape.

Segments and joints

Identify present segments and articulations without imposing a uniform digit template.

Observed structural layout

Record identifiable segments, joints and measurement landmarks.

  1. Which segments and joints are established for this finger, and which are inferred or unobserved? provenance
  2. What are the measured segment lengths or overall length, using which landmarks and posture? measurement

Tip, pad and nail

Locate the surfaces involved in touch, support and tool contact.

Local contact geometry

Describe the fingertip, pad and nail where present, including coverings that affect contact.

  1. Which fingertip, pad, side or nail surface would contact the object in the proposed task? boundary
  2. What local dimensions, nail projection or coverings affect that contact or fit? measurement
Movement and task contribution Describe demonstrated movement and the finger's role in specific hand actions.

A finger's usefulness depends on joint-specific movement and coordinated participation, which cannot be inferred from appearance.

Joint-specific mobility

Record movement direction, extent and assessment conditions.

Demonstrated movement

Distinguish self-generated movement from externally assisted movement and untested capability.

  1. Which identified joints were observed moving, in which directions and through what measured range? measurement
  2. Was the movement active, assisted or passively assessed, and what wrist posture and neighbouring-digit movement accompanied it? provenance

Functional participation

Connect digit movement and contact to an observed task.

Finger role in task

Record the finger's individual contribution without assigning it the outcome of the whole hand.

  1. During the observed task, did this finger point, tap, oppose another digit, support an object or contribute to grasping? definition
  2. What outcome was attributable to this finger, and what depended on other digits, the wrist or assistance? boundary
  3. What task conditions must remain comparable before this performance can inform another interaction? action
Local condition and sensation Capture visible condition and reported experience with location and time.

Appearance, discomfort and sensory experience provide different evidence about finger state and must remain distinguishable.

Surface and shape observations

Record visible local changes without converting them into diagnoses.

Local condition observation

Locate changes in skin, nail, contour or alignment and retain observation limitations.

  1. What changes in skin integrity, nail appearance, contour, colour or alignment are observable, and where? measurement
  2. When and under what lighting, posture or covering conditions was the observation made, and is there a comparable earlier observation? provenance

Reported experience

Represent sensation and discomfort as reports or documented assessments.

Sensation and discomfort record

Preserve the person's account and distinguish unassessed sensation from an absence of symptoms.

  1. What pain, numbness, tingling or altered touch is reported, at which part of the finger and under what conditions? measurement
  2. Does this record come from the person's report or a documented assessment, and when was it obtained? provenance
Finger interaction constraints Determine what proposed contact, movement or loading is supported by available authorization and evidence.

Recognising a finger or observing movement does not establish that manipulating, loading or instrumenting it is appropriate.

Contact and loading

Relate a proposed physical interaction to the specific finger surface and recorded limits.

Proposed interaction envelope

Specify intended contact, movement and loading while leaving unsupported limits unknown.

  1. Where would the proposed interaction contact the finger, and what force, pressure, movement or duration would it involve? action
  2. Which recorded restrictions apply to that surface, joint or task, and what source establishes them? provenance

Authorization and reassessment

Connect permission and changing finger state to action decisions.

Action readiness

Record whether a proposed interaction may proceed and what unresolved information prevents a decision.

  1. Has the person authorized this specific finger interaction, and can they communicate withdrawal or discomfort during it? action
  2. What missing evidence or change in finger condition requires pausing the interaction or obtaining an appropriate assessment? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.

A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.

Reported evidence

Findings from the breadth pass, kept separate from the structural claims.

Kinds and varieties

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • thumb (pollex; digit 1)
  • index finger (digitus secundus; digit 2)
  • middle finger (digitus medius; digit 3)
  • ring finger (digitus annularis; digit 4)
  • little finger (digitus minimus; digit 5)
  • supernumerary / polydactyl digit
  • prosthetic / robotic finger
  • non-human primate finger (including grasping hallux in some species)
  1. Which of these kinds and varieties hold for the sense of finger this model covers, and on what evidence? provenance

Identifiers and schemes

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

  • Wikidata - Q620207 - finger (anatomical structure)
  1. Which of these identifiers and schemes hold for the sense of finger this model covers, and on what evidence? provenance

Sources

  1. Anatomy of the Human Body: The Hand - Classical osteology of metacarpals and phalanges; naming of the five digits.

What the second pass must settle

  • Does the registry intend finger to include the thumb and non-human hand digits, or should either be covered through a neighbouring model?
  • What proximal anatomical boundary should define a finger consistently for measurements and ownership of shared hand structures?
  • How should congenital variation, joined digits, partial absence and reattachment affect digit identity and model boundaries?
  • Which measurement and assessment protocols provide comparable evidence for finger movement, sensation and task contribution?
  • Which authoritative sources should establish task-specific interaction limits and reassessment criteria without treating observed capability as proof of safety?