imu.md

session.imu

Inertial-measurement-unit events from the glasses. V1 exposes head-up / head-down position only; acceleration and orientation events are wire-protocol future work.

The phone-side runtime forwards IMU samples from the glasses; the SDK module is a thin pass-through over the bridge.

Source: mobile/modules/miniapp/src/modules/imu.ts

---

Quick start

import {MiniappSession, createTransport} from "@mentra/miniapp"

const session = new MiniappSession({transport: createTransport()})
await session.connect()

const unsub = session.imu.onHeadPosition((data) => {
  if (data.position === "up") {
    console.log("user looked up")
  } else {
    console.log("user looked down")
  }
})

// later
unsub()

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API

onHeadPosition(handler) — UnsubscribeFn

Subscribes to head-position events from the glasses' IMU.

Handler signature: (data: HeadPositionData) => void

interface HeadPositionData {
  position: "up" | "down"
}

Returns: UnsubscribeFn — call to detach.

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Errors

This module declares no synchronous throws and no stream-side error events. Subscription rejection (if any) surfaces through the generic session error channel.

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Wire-level reference

For host implementors — this module is stream-only.

Subscribe	Stream type	Payload
onHeadPosition	HEAD_POSITION	HeadPositionData

Acceleration and orientation events are not yet defined in the wire protocol.

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Tests

no integration tests yet