whitney_wrench — DRIVE pegtactile op

• Data kinds: table × text × scalar × scalar × scalar × scalar → table

• Call: import fullseye as fs; fs.ledger.whitney_wrench(kp, state: 'str', theta: 'float', depth: 'float', mu: 'float', fn_tip: 'float', fn_mouth: 'float' = 0.0, g=None) -> 'dict' (to call the implementation directly, import pegtactile; pegtactile.whitney_wrench(kp, state: 'str', theta: 'float', depth: 'float', mu: 'float', fn_tip: 'float', fn_mouth: 'float' = 0.0, g=None) -> 'dict'; from the registry, opsdrive.get("whitney_wrench"))

Usage

Closed-form contact wrench (Whitney's quasi-static plane, synthetic with ground truth): for a peg with tilt θ (top of the axis toward +x) and tip depth depth (from the mouth plane), applies the normal forces fn_tip, fn_mouth and downward-sliding Coulomb friction μ, with state = "one_point" (tip rim on the −x wall) / "mouth" (shank on the +x rim of the narrowest section) / "two_point" (both). For two points, the shank also touches the rim at depth = W + l₂(θ) (closed form). g is the grasp point (if omitted, peg length − 8 mm along the axis from the tip). Returns F, M_g (about the grasp point), g, tip, axis, points. Raises ValueError: state outside the vocabulary, θ outside (0, π/2), depth, μ or a normal force not finite or negative.

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• poc_peg_insertion_tactile — py -3.11 examples/poc_peg_insertion_tactile.py

Ops the type connects to (they accept table as input)

course_layout · course_occupancy · course_contains · world_build · world_camera · world_move · lidar_scan · rss_longitudinal_same

Same category (pegtactile)

pad_params · pad_context · peg_wrench_to_pad_loads · pad_loads_to_peg_wrench · pad_shear_asymmetry · pad_marker_displacement · pad_tactile_frame · pad_tactile_read

*Provenance: pegtactile.py — DRIVE operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.