pad_marker_displacement — DRIVE pegtactile op

• Data kinds: scalar × signal × table → table

• Call: import fullseye as fs; fs.ledger.pad_marker_displacement(P: 'float', q_uv, pad: 'dict', ctx=None, pts=None, torsion: 'float' = 0.0, torsion_model: 'str' = 'partial_slip') -> 'dict' (to call the implementation directly, import pegtactile; pegtactile.pad_marker_displacement(P: 'float', q_uv, pad: 'dict', ctx=None, pts=None, torsion: 'float' = 0.0, torsion_model: 'str' = 'partial_slip') -> 'dict'; from the registry, opsdrive.get("pad_marker_displacement"))

Usage

Membrane surface displacement at the marker positions (closed form + Cerruti convolution): shear |q| in direction φ is the x-direction Mindlin field rotated by φ, u(p) = R(φ) u_x(R(−φ)p) (the kernel is an isotropic half-space, so it is closed under rotation); the radial displacement ūr of the normal load (Johnson eq. 3.41b) and the torsion field are added. The torsion field is partial slip if torsion_model="partial_slip" (default, since 2026-10-06) (numerical solution of cuttouch.torsion_partial_slip, slipping from the edge annulus), or the no-slip field used up to 0.4.0 if "no_slip" (tactorque.torsion_stick_field). When the torsion exceeds full slip, the membrane cannot carry any more torsion, so the field of the table's last row (stick circle = 1 annulus) is drawn and the torsion_slipping flag is set. pts are the marker centers (px; if omitted, the reference positions in ctx). Returns u_m (N, 2) [m], hz, mp (Hertz and Mindlin tables), phi, Q, torsion, torsion_model, torsion_ratio, torsion_slipping. Full slip (|q| ≥ μP) is flagged by mp['slipping'] (field with c = 0). Raises ValueError: P ≤ 0 (pad not in contact), q is not 2 finite components, misspelled torsion_model.

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_knife_tactile_toughness — py -3.11 examples/poc_knife_tactile_toughness.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_tactile_frame · pad_tactile_read · contact_candidates


*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.