A calibration block in the footprint of a 96-well microplate. It sits on a liquid handler's deck and answers one question no balance can: is the pipetting head parallel to the deck? A 96-cell sensing foil records the order in which tips make contact — and that order becomes a per-tip z-delta map in microns.
The operator tares the foil, then lowers the head. A tilted head lands unevenly: the lowest tip touches first, the highest last. Each of the 96 cells reports a force delta in ADC counts at 10–50 Hz; ranking the contacts by arrival converts tilt into a z-step per tip. An onboard accelerometer separately confirms the block itself is level — so head tilt is never confused with a tilted block. (Tilt exaggerated for clarity.)
In LabBoxZero Hub's Live Calibration page, the 96 cells paint in as the head lands — a level head fills the plate almost at once; a tilted head sweeps across it like a wave. Two heatmaps render live: Contact Sequence (shown here) and Z-Delta Topology. A 96-channel head lands in one descent; an 8-channel head descends column by column.
96 / 96 wells active · max z-delta 350 µm ≤ 450 µm · no maxed-out well · block level ✓
z-drift vs. previous cal: +12 µm · fitted plate tilt recorded (across rows, across columns, residual)
FAIL if any tip's z-delta exceeds 450 µm — or any well maxes out its travel, because a beyond-range tip is unmeasurable and risks damaging the foil. Known-dead channels can be excluded as ignored wells before the verdict.
Inside the block, a data-acquisition module scans the matrix and reads the accelerometer, streaming framed snapshots over an internal serial link to a communication module (WiFi / BLE / WebSocket) — or straight to the Hub PC over USB serial. The Hub backend tares, thresholds, ranks contacts, and pushes live heatmaps to the browser; saving a session writes a calibration record that can carry a 21 CFR Part 11 e-signature.