tether_simulate — DRIVE ball op

• Data kinds: none → table (an op determined by its arguments alone — it takes no image or data input)

• Call: import fullseye as fs; fs.ledger.tether_simulate(p0, v0, handle, L: 'float', t_end: 'float', dt: 'float' = 0.001, g: 'float' = 9.81, mass: 'float' = 0.01) -> 'dict' (to call the implementation directly, import ballistics; ballistics.tether_simulate(p0, v0, handle, L: 'float', t_end: 'float', dt: 'float' = 0.001, g: 'float' = 9.81, mass: 'float' = 0.01) -> 'dict'; from the registry, opsdrive.get("tether_simulate"))

Usage

> This operator's description has not been translated yet. The original text follows as it is.

伸びないひも(長さ L)で手元 `handle` に繋がれた質点の運動(けん玉の玉)。

`handle` は (3,) の固定点か、時刻 → (3,) の関数。各ステップで自由落下を進め、|p − h| > L になったら球面へ射影して

外向きの相対径方向速度を消す(片側拘束: ひもは引くだけで押さない)。その瞬間に失う運動エネルギー ½ m v_r² を "snap_loss" に

積む。張力の推定 = 射影で消した径方向の速度変化 × m / dt(≥ 0)。返り値 ``{"t", "p", "v", "tension", "taut" (bool),

"snap_times", "snap_loss", "energy"}``。定理の門: |p − h| ≤ L + 1e-9、張力 ≥ 0、手元が固定なら力学的エネルギーは

snap の瞬間以外で不変(RK 誤差の範囲)、小振幅の周期は 2π√(L/g)。

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_kendama — py -3.11 examples/poc_kendama.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 (ball)

ball_params · impact_params · flight_vacuum · flight_ode · flight_simulate · flight_state_at · magnus_lift_coefficient · drag_coefficient_sphere


*Provenance: ballistics.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.