US 6,876,947 · Granted 2005-04-05
The Patent That Taught Your Fitness Tracker Your Walking Style
A runner's stride and pace are as unique as a fingerprint. This patent teaches devices how to learn your personal walking or running rhythm during a single outing, then use that one-time calibration to accurately track all your future workouts—no fancy equipment needed, just the natural timing of your feet hitting the ground.
The plain-English version
What it protects
The claim covers a method for calibrating activity-monitoring devices by measuring how long a user's foot stays in contact with the ground during one initial workout session, establishing a personalized mathematical relationship between that contact time and their pace, and then using that single calibration constant to power all subsequent activity tracking. What's protected here is the specific technique of using foot contact time as the anchor point for user-specific calibration, rather than relying on multiple outings or generic population averages.
Why it matters
Before smartphones packed motion sensors, fitness devices struggled to accurately track running and walking because every person's biomechanics are different. This patent solved a real problem: how to make a wearable device learn someone's unique gait signature in a single session, then use that knowledge to deliver accurate distance, pace, and activity data going forward. It became foundational technology for early fitness trackers and running watches that needed to work reliably across different body types and running styles without constant recalibration.
Real-world use
When you first strap on a fitness watch and it asks you to walk or run for a short calibration period, it's capturing the foot-contact patterns this patent describes—teaching itself your personal biomechanics so it can track your speed and distance accurately for months afterward.
Original USPTO abstract
In one embodiment, a method includes steps of: (a) identifying an average foot contact time of a user during a first outing; (b) identifying an average pace of the user during the first outing; (c) defining a relationship between foot contact times of the user and corresponding paces of the user, wherein the relationship is based upon the average foot contact time and the average pace identified during the first outing, and wherein no other average foot contact times and no other average paces identified during any different outings by the user are used to define the relationship; and (d) calibrating at least one device that monitors activity of the user in locomotion on foot based upon the defined relationship between foot contact times of the user and corresponding paces of the user. In another embodiment, a method includes steps of: (a) determining a single user-specific calibration constant that defines a relationship between foot contact times of a user and corresponding paces of the user, wherein no other user-specific calibration constants are used to define the relationship; and (b) calibrating at least one device that monitors activity of the user in locomotion on foot based upon the relationship between foot contact times of the user and corresponding paces of the user that is defined by the single user-specific calibration constant.
Patent details
- Publication number
- US 6,876,947
- Filing date
- 2000-08-21
- Grant date
- 2005-04-05
- Assignee
- Fitsense Technology, Inc.
- Inventor(s)
- DARLEY JESSE, OHLENBUSCH NORBERT
- CPC class
- G01C22/006
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