punch_pressure — DRIVE tactorque op

• Data kinds: matrix × matrix × scalar × scalar → matrix

• Call: import fullseye as fs; fs.ledger.punch_pressure(X, Y, a: 'float', P: 'float' = 0.0, M1=(0.0, 0.0), pitch: 'float | None' = None, sub: 'int' = 4) -> 'np.ndarray' (to call the implementation directly, import tactorque; tactorque.punch_pressure(X, Y, a: 'float', P: 'float' = 0.0, M1=(0.0, 0.0), pitch: 'float | None' = None, sub: 'int' = 4) -> 'np.ndarray'; from the registry, opsdrive.get("punch_pressure"))

Usage

Pressure [Pa] of a flat circular punch (radius a [m]): p = P/(2πa√(a²−r²)) + 3(M1_x x + M1_y y)/(2πa³√(a²−r²)) (r < a, 0 outside). Term 1 = Johnson 1985 Eq. 3.34; term 2 = the antisymmetric term satisfying ∫ (x, y) p dA = M1 (derivation in the module docstring, confirmed numerically by a gate). Passing pitch averages each pixel over sub×sub subsamples (reduces the grid error of the 1/√ singularity at the edge; with 4×4, Σ p h² matches P within 0.6 %, measured). Raises ValueError: a ≤ 0, P < 0, X and Y differ in shape, |M1| > Pa/3 (the contact separates: the linear formula no longer holds, fail-closed).

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_tactile_dipole_torque — py -3.11 examples/poc_tactile_dipole_torque.py

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

world_camera · lidar_scan · relative_motion · foe_from_motion · flow_from_depth_motion · ttc_truth · world_materials · mesh_signed_volume

Same category (tactorque)

punch_surface_uz · hertz_pressure_shifted · ellipse_pressure_shifted · pressure_first_moment · boussinesq_kernel · boussinesq_surface_displacement · surface_divergence_closed_form · tilt_shear_field

*Provenance: tactorque.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.