cuttouch op• Data kinds: scalar × scalar × table → table
• Call: import fullseye as fs; fs.ledger.torsion_partial_slip(M: 'float', P: 'float', pad: 'dict | None' = None, ctx=None, field: 'bool' = False, na: 'int' = 64, from_no_slip_read: 'bool' = False, contact: 'dict | None' = None) -> 'dict' (to call the implementation directly, import cuttouch; cuttouch.torsion_partial_slip(M: 'float', P: 'float', pad: 'dict | None' = None, ctx=None, field: 'bool' = False, na: 'int' = 64, from_no_slip_read: 'bool' = False, contact: 'dict | None' = None) -> 'dict'; from the registry, opsdrive.get("torsion_partial_slip"))
Partial slip when a torsion M [N·m] about the normal is applied to a spherical pad (Hertz, normal force P): stick radius c, twist angle β, and the ratio to full slip.
The numerical solution is described at the top of the module (influence matrix of na rings; a single dimensionless curve computed only once). Returns: ratio = |M| / ((3π/16)μPa), c_over_a, beta (twist angle under partial slip [rad]), beta_no_slip = 3M/(16Ga³) (Reissner–Sagoci), read_bias = β/β_no_slip (the factor by which M is overestimated when read with the no-slip relation), a / p0 / M_full, slipping (ratio ≥ 1 = full slip. A flag, not an exception —— slipping is a state that occurs, not an input error. β is undefined, so nan), readable (the stick circle contains the reading kernel r < 0.6a). With field=True, it also returns, on the grid of ctx (pegtactile.pad_context), the surface displacements ux / uy [m] obtained by convolving the circumferential traction with the Cerruti kernel, and u_markers (N, 2) [m] at the reference positions of the markers (for synthesis. Not produced under full slip). With from_no_slip_read=True, M is treated as a value read with the no-slip relation (Reissner–Sagoci, torsion_model="no_slip" of pegtactile.pad_tactile_read), converted to the partial-slip M, and the same table is returned (M = corrected value, M_read = the passed reading. If the reading exceeds the full-slip image, M = full-slip torque and slipping). ratio_table_max is the ratio in the last row of the table (beyond this, the stick circle is smaller than one ring and no field is produced). Instead of a pad, passing contact={"a": 接触半径 [m], "mu": 摩擦係数, "G": せん断弾性率 [Pa]} returns the same numerical solution as a Hertz contact with known contact radius (pressure p₀√(1 − r²/a²), p₀ = 3P/(2πa²)) —— the correction of Mz in tactorque.torque_decompose goes through this entry point (field=True needs the pad grid, so only with pad). Raises ValueError: P ≤ 0 / non-finite, M non-finite, pad not a table of pegtactile.pad_params, both pad and contact / neither, contact's a / mu / G not positive finite, field=True without pad, na < 24.
• 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.
• poc_knife_tactile_toughness — py -3.11 examples/poc_knife_tactile_toughness.py
• poc_tactile_dipole_torque — py -3.11 examples/poc_tactile_dipole_torque.py
table as input)course_layout · course_occupancy · course_contains · world_build · world_camera · world_move · lidar_scan · rss_longitudinal_same
cuttouch)knife_load_from_pads · toughness_from_pads
*Provenance: cuttouch.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.