How Tailways actually works
Specifications and honest limits, for anyone deciding whether this is real engineering.
1. Why not heart rate
A PPG sensor, the kind used in most wearables, needs consistent skin contact to get a clean signal. On a furred animal that means shaving a patch or fitting a tight chest strap, neither practical for daily wear.
A dog's own movement also corrupts that signal far more than it does on a mostly still human wrist. And a single heart rate number is a weak, indirect proxy for emotional state on its own. We chose motion based sensing because it's the more reliable signal for this problem, not the more convenient one.
2. The sensor
A 24GHz radar module that sends out a continuous wave and reads the tiny reflections back, sampled continuously.
| Frequency | 24GHz continuous wave |
| Range gates | 9, each tracked independently |
| Per-gate output | Motion energy, static energy |
| Sampling | Continuous |
3. Classification
A rolling window of features, total motion energy, motion variance, stillness ratio, how often movement suddenly changes, and a breathing rate estimate, feeds a classifier with five possible states, plus a confidence score for each reading.
A state only changes once several windows in a row agree, so the reading doesn't flicker between adjacent states.
Each dog's own baseline is learned over the first several days of wear, since a greyhound's stillness and a terrier's stillness are not the same signal.
4. The intervention
Four small vibration motors run rhythmic patterns paced to a slow breath or a resting heartbeat.
It's a closed loop. The anxiety score is watched throughout a session, and the session ends early if that score comes down before the maximum duration is reached.
5. Safety architecture
All limits below are enforced in firmware, not policy.
| Limit | Threshold | Action when hit | Recovery |
|---|---|---|---|
| {{ row.label }} | {{ row.value }} | {{ row.action }} | {{ row.recovery }} |
The safety monitor runs on the real-time core at the highest task priority in the system and cannot be pre-empted by any other process, including the classifier and all network activity. Safety is not a check that runs when there is time spare. It is the task everything else yields to.
Intensity levels
| Level | Motor power | Intended for |
|---|---|---|
| {{ row.level }} | {{ row.duty }} | {{ row.use }} |
There are eight therapy patterns: Heartbeat Rhythm, Breathing Pulse, Spine Wave, Comfort Hold, Anxiety Wrap, Progressive Calm, Focus Pattern, and Sleep Inducer.
6. What we don't claim
- No medical or veterinary claim of any kind.
- No vital sign measurement. It's motion and breathing pattern only, not heart rate.
- Any data shown states its sample size, and nothing here has been validated at scale.
- Long term effects of daily wear are still unproven.
7. Who's building this
Tailways is built by Abdul Sattar, founder and chief architect, and Bushra Ramsha, who builds the app and this site. The firmware and the harness are his; the software you'll use every day is hers. The first prototype ran for twenty-nine hours on a real dog before anyone else saw it. When you apply, he reads it. When the harness is fitted, it's fitted by the person who wrote the code running on it.
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