iOS CoreMotion - 计算高度差异 [英] iOS CoreMotion - Calculating Height Difference

问题描述

当iPhone使用CoreMotion的数据移动时，是否可以计算高度差？

Is it possible to calculate the difference in height when an iPhone moves using the data from CoreMotion?

例如，保存iPhone的初始位置，然后移动iPhone会产生新的位置。我有兴趣检测iPhone的高度是否从其初始位置移开。我不需要绝对单位，只需要一个相对值来表示高度从原始高度变化的百分比。

For example, the initial position of the iPhone is saved, then the iPhone is moved which results in a new position. I am interested in detecting if the height of the iPhone moved from its initial position. I don't need absolute units, just a relative value indicating what percentage the height has changed from its original height.

let manager = CMMotionManager()

// Save initial attitude
var initialAttitude = manager.deviceMotion.attitude

if manager.deviceMotionAvailable {
manager.startDeviceMotionUpdatesToQueue(NSOperationQueue.mainQueue()) {
    [weak self] (data: CMDeviceMotion!, error: NSError!) in

    // Get the difference between the initial and new attitude
    data.attitude.multiplyByInverseOfAttitude(initialAttitude)

    // Is there a way to calculate the relative change in height?

    }
}

推荐答案

不，这是不可能的。抱歉。

No, this isn't possible. Sorry.

有一篇很好的论文解释了为什么这是不可能的，但我现在找不到它。如果我发现它，我会发布一个链接。

There is a nice paper explaining why this isn't possible but I' can't find it at the moment. If I find it I'll post a link.

但是，通过使用加速度计等来测量移动的距离...是不可能的，主要是因为噪音通过双重整合大大增加。

But yeah, measuring distance moved by just using the accelerometer etc... isn't possible due mainly to noise that is vastly increased by double integration.

另外，我认为你很困惑态度和海拔高度。

Also, I think you're confusing Attitude and Altitude.

前者是描述方向的对象使用滚动，俯仰，偏航等设备...... CMDeviceMotion 的态度属性。

The former is an object describing the orientation of the device using roll, pitch, yaw, etc... The attitude property of the CMDeviceMotion.

后者是海拔高度，不能通过iOS获得。您可以在iOS中获得的唯一海拔高度是地球上特定点高于海平面的高度。但你无法获得设备的高度，只能获得地面的高度。

The latter is the height above sea level and isn't available through iOS. The only altitude you can get in iOS is the height a particular point on the earth is above sea-level. But you can't get the device altitude, just the ground's altitude.

无论哪种方式，它仍然无法实现。

Either way, it's still not possible.

这不是一篇论文。这是一段视频。

It wasn't a paper. It was a video.

https：/ /www.youtube.com/watch?v=_q_8d0E3tDk

这篇关于iOS CoreMotion - 计算高度差异的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！