Andrdoid Sensors Overview (探测器概述)二

Introduction to Sensors

介绍传感器

The Android sensor framework lets you access many types of sensors. Some of these sensors

are hardware-based and some are software-based. Hardware-based sensors are physical components built into a handset or tablet device. They derive their data by directly measuring specific environmental properties, such as acceleration, geomagnetic field strength, or angular change. Software-based sensors are not physical devices, although they mimic hardware-based sensors. Software-based sensors derive their data from one or more of the hardware-based sensors and are sometimes called virtual sensors or synthetic sensors. The linear acceleration sensor and the gravity sensor are examples of software-based sensors.

Android sensor framework 让你使用多种传感器。有基于硬件和基于软件的。基于硬件的传感器是内置于设备中的物理组件。它们直接测量具体的环境属性来得出数据，例如加速度，地磁场强度，或者角的变化。基于软件的传感器你不是物理设备，尽管它们模拟硬件传感器。软件探测器通过一个或者多个硬件传感器来得出数据，有时称为虚拟传感器或者合成传感器。线性加速度传感器和重力传感器是软件传感器的例子。

Table 1 summarizes the sensors that are supported by the Android platform.

表1 总结了android 平台支持的传感器。

Few Android-powered devices have every type of sensor. For example, most handset devices and tablets have an accelerometer and a magnetometer, but fewer devices have barometers or thermometers. Also, a device can have more than one sensor of a given type. For example, a device can have two gravity sensors, each one having a different range.

少有android 设备每种传感器都有。例如，大部分手机设备和平板有一个加速计和一个磁力计，但是较少设备有气压计或温度计。一个设备也可以有一个以上的同类传感器，如果可以用两个不同范围的重力传感器。

Table 1. Sensor types supported by the Android platform.

表1。Android 平台支持的传感器种类。