Research
Before building anything, I researched what exists, what failed, and why. This page is kept honest and updated as the project learns more — sources linked throughout, confidence levels flagged where the evidence is thin.
The alternatives, at a glance
Every wearable I could find that warns blind and low-vision users about obstacles above cane height. Head-height fit is my rating of how well each covers this project's exact job — warning about branches and overhangs on a trail — based on the write-ups below, not hands-on testing.
Ambutech iGlasses
Ultrasonic glasses · temple vibration
- Price
- ~$120–150
- Sensing
- Ultrasonic, ~3 m
- Weight
- <85 g
The lesson: Head-mounted haptics work — and looking like normal eyewear is an adoption feature. Weakness: wide beam causes indoor false-alarm storms.
WeWALK Smart Cane 2
Smart cane handle · beeps or vibration
- Price
- $850 + subscription
- Sensing
- Ultrasonic, ~5 m
- Weight
- ~280 g handle
The lesson: A swinging cane is a false-positive machine; gen-1 users learned to ignore it. Adjustable sensitivity is the most-used setting.
biped.ai NOA
Camera AI shoulder harness · 3D audio
- Price
- ~€5,000 + subscription
- Sensing
- Cameras 170°, ~10 m
- Weight
- 950 g
The lesson: Fixed false alarms with trajectory-filtering AI, and users love the information design. Bulk, price and battery are the top complaints.
.lumen Glasses
Camera/LiDAR headset · forehead haptics
- Price
- €9,999
- Sensing
- Cameras + LiDAR
- Weight
- Headset-class
The lesson: Validates the forehead as a haptic feedback site — at 100× this project’s budget.
Sunu Band
Wrist sonar band · vibration
- Price
- Was $299
- Sensing
- Ultrasonic, ~5.5 m
- Weight
- ~40 g
The lesson: The beam points where your arm swings, not where you’re going. Distance→pulse-rate encoding was well liked; false positives and build quality killed it.
iMerciv BuzzClip
Lapel clip · vibration
- Price
- Was CAD $250–330
- Sensing
- Ultrasonic, 1–2 m modes
- Weight
- ~50 g
The lesson: The closest analog — and a warning: vibrations too weak and too frequent, no spatial info, zero measured mobility improvement in a 13-person study.
Ara by Strap Tech
Chest strap · haptics
- Price
- $2,750
- Sensing
- Ultrasonic + LiDAR
- Weight
- Unknown
The lesson: Dubious delivery record, no independent reviews. A reminder that shipping reliably matters more than sensor count.
The common thread: every failed device failed on false alarms and lost trust, not on range or price. The full analysis, with sources — including why nothing affordable serves this niche anymore — is in the write-ups below.
The write-ups
Market scan: why nothing on the market does this anymore
The cheap wearables closest to this concept are discontinued; the survivors cost $850–€9,999. Every failed product failed the same way: false alarms.
What real users of similar devices taught me
Primary user voices — AppleVis reviews, AFB evaluations, blind bloggers, a 13-participant study — distilled into what gets a device adopted and what gets it abandoned.
The sunlight problem: why cheap laser sensors fail outdoors
The cap points at branches silhouetted against bright sky — the worst case for infrared distance sensors. Why every shipped assistive wearable chose ultrasound instead.
Choosing the sensors (and the hardware around them)
Four research passes, a head-to-head verification, and a decision: which sensors made the cut for Prototype 1, which were rejected, and why.
The hypotheses: what Prototype 1 is actually testing
One main hypothesis, fourteen sub-hypotheses, pass/fail thresholds set before testing. A killed hypothesis is a successful experiment.