Distance edges are invisible, so standing out of range and a missed gesture look like the same zero

What it is

The far and near edges of interaction distance have no ticks in the air. A step back or a thicker cushion drops the gesture from “stable” to “the system did nothing.” That looks identical to a misread, a bad slice, or never having engaged: an action, zero feedback. People change the move. They do not first change stance. Invisible radial edges are why a distance problem is misdiagnosed as a gesture problem. How the left–right–up–down walls of a volume are perceived is a further spatial layer. This is the unseen ruler along the camera axis as people walk nearer and farther.

Why it happens

Vision does not supply a percept of “you are 2.4 m from the depth camera.” Furniture and screen size give a coarse room scale, not the knee of the sensing curve. Past the far edge, joints are still reported, jitter exceeds the move, the recognizer emits nothing. Past the near edge the hand leaves the frame or blows out, and the emission is the same nothing. That nothing and “the wave did not match the template” are the same zero at the event layer. With no independent channel saying “stance,” people repair with vocabulary strategies: go bigger, do it twice, switch gestures. Bigger moves have worse signal-to-noise on the far edge, and failure tightens. The near edge may be read as “I am blocking the screen”; people step sideways and distance gets worse.

Studying it

With no hints, have people ease back or lean in from a comfortable distance until the first failure, then ask what they think caused it. Code: stance, gesture, broken system. At the same failure point add a distance hint and see whether attribution flips. Log distance of the last step before failure against the knee of the sensing curve. Do not put “stand here” on the floor; that makes the invisible edge visible and hides natural attribution.

Where it stops holding

A headset can see one's own hand vanish from view, so the near edge is more perceptible than with a room camera; the far edge (arm straight) still lacks ticks. Some people use sharpness of screen content as a distance cue—that is display focus, not gesture-sensing distance, and the two rulers will not agree. Floor projection or a carpet pattern can be a coarse scale and dies in the next room. Silent out-of-range is the default; once silent, attribution data will lean toward gesture and fault. That is not users being dim.

Applying it

• Do not expect people to find the sensing knee. Treat failure as stance-and-gesture inseparable until you emit a stance signal.
• In usability tests ask “why do you think nothing happened,” and count “my gesture was wrong” separately from “I stood too far.”
• Floor stickers may help at install time. They are not a runtime boundary. Runtime must say the edge at the moment of failure.

Related

• Same group: C4.10.1 Interaction distance should sit inside capture range · C4.10.2 The coordinate anchor decides consistency after movement · C4.10.4 Boundary state must be expressed and distinguishable from recognition failure
• Adjacent: C4.22 Perceiving interaction-volume boundaries · C4.03 Gesture onset and offset detection
• Search: invisible boundary · too far · range failure