电阻应变式传感器测量加速度的原理

一般用于称重传感器或者压力传感器.

灵敏度、线性、高低温蠕变,精度等级、机械滞后.

把电阻做成贴片,四片相同阻值的贴片分别两横两竖地,贴在几何尺寸均匀的金属弹性体的表面上,它们组成一个全桥式测量电路,电桥的输入端接上恒定的直流电源,输出端就是金属体受力时的输出信号了.这种桥式测量电路,可以灵敏地测量极微小的电阻变化.当物体放于秤盘上,弹性体受物体重力的作用,弹性体便产生弹性形变,粘在其表面的电阻应变片随其同步地变形,因而改变了它们的电阻值,电阻应变片的长度L,截面积S,电阻率P均随之发生变化.由于电阻应变片组成的桥式电路是平衡的,电阻应变片的电阻变化会引起电桥的不平衡,从而输出电压信号,该信号与物体的质量m成正比.通过弹性元件,电阻应变片和测量电路从而实现了电信号间的线性转变.该信号经放大电路放大输出到A/D转换器,转换成便于处理的数字信号输出到CPU运算控制.CPU不断扫描键盘和各种功能开关,根据键盘命令以及程序将这种结果输出到显示器,直至显示这种结果.

缺点：不得在外界环境变化比较大的地方使用
优点：便宜

有电阻应变原理的位移计,所有电阻应变式传感器都是把要测量量和弹性体的变形联系起来

Resistance is a strain sensor using electrical resistance strain gages will be converted to strain sensor resistance changes, any non-variable as long as it can to try to transform strain, can use resistance strain gages for measurement. For example, in the measurement of time, can be pasted in the resistance strain gages can withstand the force measured elastic element, when in the role of the elastic element, it will have strain, strain through this paste to transfer resistance strain gages, so that the resistance strain gages change. due to the strain and elastic element by the affordability of proportion to the size, it measured the resistance strain gages can be measured resistance change in the size of effort. sensor resistance is the basic tenets of the measured non-resistance values converted into electricity, and by measuring the resistance to achieve the purpose of measuring non-electricity. many of the types of such sensors can be broadly divided into two categories: resistance strain and the potential of sensor using a resistive sensors can be measured deformation, stress, displacement, acceleration and temperature, and other non-consumption parameters.

以电阻应变计为转换元件的电阻式传感器.电阻应变式传感器由弹性敏感元件、电阻应变计、补偿电阻和外壳组成,可根据具体测量要求设计成多种结构形式.弹性敏感元件受到所测量的力而产生变形,并使附着其上的电阻应变计一起变形.电阻应变计再将变形转换为电阻值的变化,从而可以测量力、压力、扭矩、位移、加速度和温度等多种物理量.常用的电阻应变式传感器有应变式测力传感器、应变式压力传感器、应变式扭矩传感器（见转矩传感器）、应变式位移传感器（见位移传感器）、应变式加速度传感器（见加速度计）和测温应变计等.电阻应变式传感器的优点是精度高,测量范围广,寿命长,结构简单,频响特性好,能在恶劣条件下工作,易于实现小型化、整体化和品种多样化等.它的缺点是对于大应变有较大的非线性、输出信号较弱,但可采取一定的补偿措施.因此它广泛应用于自动测试和控制技术中. 电阻应变式传感器 传感器中的电阻应变片具有金属的应变效应,即在外力作用下产生机械形变,从而使电阻值随之发生相应的变化.电阻应变片主要有金属和半导体两类,金属应变片有金属丝式、箔式、薄膜式之分.半导体应变片具有灵敏度高（通常是丝式、箔式的几十倍）、横向效应小等优点.