granular op• Data kinds: signal × signal × scalar → table
• Call: import fullseye as fs; fs.ledger.hopper_discharge_rate(mass_below, times, mass_total: 'float', *, lo: 'float' = 0.2, hi: 'float' = 0.8) -> 'dict' (to call the implementation directly, import granular; granular.hopper_discharge_rate(mass_below, times, mass_total: 'float', *, lo: 'float' = 0.2, hi: 'float' = 0.8) -> 'dict'; from the registry, opsdrive.get("hopper_discharge_rate"))
Discharge rate [kg/s] from the series m(t) of mass below the floor plate — fits a line only to the band from lo to hi of the total mass (excluding start-up and the final stop; Beverloo's steady-flow assumption). Returns: rate, n_frames (frames in the band), t_range, rms [kg]. Raises ValueError: fewer than 3 frames in the band (discharge too fast to leave any frames — does not silently return a 2-point slope) / timestamps not monotonic.
• 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_granular_heap_repose — py -3.11 examples/poc_granular_heap_repose.py
table as input)course_layout · course_occupancy · course_contains · world_build · world_camera · world_move · lidar_scan · rss_longitudinal_same
granular)heap_volume_cone · heap_mass · heap_volume_heightmap · beverloo_rate · beverloo_fit · discharge_synth · dispense_mass_from_video · spoon_tilt_critical
*Provenance: granular.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.