Intersection cross-cut: pendant ∩ sensor-accelerometer

Axes: form_factor × sensors

3 corpus entries disclose both tags.

Earliest disclosure: 1998-10

These entries are the direct inputs to OBVIOUSNESS_TEMPLATE.md. Any patent claim combining these two elements is anticipated or rendered obvious by the chain below.

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Williams et al. (1998) — accelerometer-based automatic fall and activity monitor for telecare (1998-10)

• id: williams-1998-automatic-fall-detector
• corpus: academic
• form factor: belt
• creator: G. Williams / K. Doughty / K. Cameron / D.A. Bradley
• disclosure: Williams G, Doughty K, Cameron K, Bradley DA. ‘A smart fall and activity monitor for telecare applications.’ Proceedings of the 20th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS), Hong Kong, 1998, pp. 1151-1154.
• ip status: unknown
• sensors: sensor-accelerometer, sensor-piezoelectric
• algorithms: algo-fall-detection, algo-activity-classification

• prior art notes: Discloses a body-worn (waist/trunk) device that automatically detects a fall from accelerometer/impact signals — distinguishing falls from normal activity — and raises a telecare alarm, without requiring the wearer to press a button. Anticipates automatic-fall-detection wearable claims combining ‘a body-worn inertial sensor’, ‘a classifier distinguishing a fall from activities of daily living’, and ‘an automatic alert on detection’. Anchor for the fall-detection cross-cut; combined with watch/pendant form-factor disclosures, makes wristworn/pendant automatic fall detection obvious under [[obviousness-template]].

• Digimon — ‘Digivice’ (worn companion-monitoring device) (1999-03-07) — digimon-digivice [fictional] — Digimon Adventure (Toei animated series, premiered 7 March 1999; derived from the 1997 Tamagotchi-style ‘Digital Monster’ virtual-pet device); a small worn/clipped device with a display that monitors …

  Fitbit Tracker (2009) — clip-on accelerometer activity and sleep monitor (2009-10)

• id: fitbit-tracker-2009
• corpus: private
• form factor: pendant
• creator: Fitbit, Inc. (James Park, Eric Friedman)
• disclosure: Fitbit, Inc. ‘Fitbit Tracker’, launched October 2009 — a clip-worn device with a 3-axis accelerometer estimating steps, distance, calories burned, active minutes, and sleep quality, syncing wirelessly to a web dashboard. (The wrist PPG heart-rate variant, Fitbit Charge HR, followed in January 2015.)
• ip status: patented
• sensors: sensor-accelerometer
• algorithms: algo-step-count, algo-calorie-estimation, algo-activity-classification, algo-sleep-staging
• prior art notes: Discloses a small body-worn (clip) device with a 3-axis accelerometer that estimates step count, distance, calories, active minutes, and sleep quality on-device and syncs wirelessly to a cloud dashboard. Anticipates consumer-activity-tracker claims combining ‘a body-worn accelerometer’, ‘on-device estimation of steps/calories/activity/sleep’, and ‘wireless sync to a remote service’ from 2009. Anchor for the step-count and consumer-sleep-tracking cross-cuts on the product side.