iphone - 检测 iPhone/Apple Watch 的物理运动

Question

我正在尝试检测用户执行的移动(向右或向左)。我们假设用户开始时将 ARM 伸到前面，然后向右或向左移动 ARM (偏离中心约 90 度)。

我已集成 CMMotionManager，并希望了解通过 startAccelerometerUpdatesToQueue 和 startDeviceMotionUpdatesToQueue 方法检测方向。

有人可以建议如何在 iPhone 上实现这个逻辑，然后在 Apple Watch 上实现吗？

Answer 1

苹果提供watchOS 3 SwingWatch sample code演示如何使用 CMMotionManager() 和 startDeviceMotionUpdates(to:) 来计算 Racket 运动中的挥杆次数。

他们的代码演示了如何检测一秒间隔运动的方向，尽管您可能需要调整阈值以考虑要跟踪的运动的特征。

func processDeviceMotion(_ deviceMotion: CMDeviceMotion) {
    let gravity = deviceMotion.gravity
    let rotationRate = deviceMotion.rotationRate

    let rateAlongGravity = rotationRate.x * gravity.x // r⃗ · ĝ
                         + rotationRate.y * gravity.y
                         + rotationRate.z * gravity.z
    rateAlongGravityBuffer.addSample(rateAlongGravity)

    if !rateAlongGravityBuffer.isFull() {
        return
    }

    let accumulatedYawRot = rateAlongGravityBuffer.sum() * sampleInterval
    let peakRate = accumulatedYawRot > 0 ?
        rateAlongGravityBuffer.max() : rateAlongGravityBuffer.min()

    if (accumulatedYawRot < -yawThreshold && peakRate < -rateThreshold) {
        // Counter clockwise swing.
        if (wristLocationIsLeft) {
            incrementBackhandCountAndUpdateDelegate()
        } else {
            incrementForehandCountAndUpdateDelegate()
        }
    } else if (accumulatedYawRot > yawThreshold && peakRate > rateThreshold) {
        // Clockwise swing.
        if (wristLocationIsLeft) {
            incrementForehandCountAndUpdateDelegate()
        } else {
            incrementBackhandCountAndUpdateDelegate()
        }
    }

    // Reset after letting the rate settle to catch the return swing.
    if (recentDetection && abs(rateAlongGravityBuffer.recentMean()) < resetThreshold) {
        recentDetection = false
        rateAlongGravityBuffer.reset()
    }
}