electrolytictiltsensorsandinclinometersprimer電解質(zhì)傾角傳感器介紹

1、Electrolytic Tilt Sensors and Inclinometers PrimerWhat Is A Tilt Sensor?The phrase 'tilt sensor' is a term, which has been widely used, and misused over the years. It is frequently employed in a generic fashion t

2、o describe a large variety of devices, which either measure, indicate, or otherwise provide a signal of some type, when tilted from (or to) a level position, using gravity as a reference. While a number of these devices

3、are indeed tilt sensors, the others fall into various categories, which by their very definition negate their inclusion. However, to make a distinction as to what actually qualifies a device as a true tilt sensor, we mus

4、t first understand what one is.A tilt sensor can be defined as a device, which produces an electrical output that varies with angular movement. Though brief and rudimentary, this definition plainly makes two pertinent po

5、ints: the device must have an electrical output, and that the electrical output must vary when tilted. With this understanding, all visual/mechanical devices such as ball-in-tube style slope indicators, pendulum protract

6、ors and bubble levels for that matter, are automatically eliminated. Also eliminated are devices, which use mercury switches and/or electro-mechanical triggers that strictly deliver on-off type outputs.Within the sensor

7、industry, the term tilt sensor becomes a bit finer. Normally it will refer strictly to the sensing element itself, devoid of any input/output conditioning electronics. Once conditioning electronics are added, the aggrega

8、te device then becomes known as an inclinometer. Although both have an electrical output, which varies with angular movement, this distinction is commonly recognized.Types Of Tilt Sensors And InclinometersThere are many

9、types of tilt sensors and inclinometers available on the market today, some whose history extends back more than 50 years. There are three major categories, which encompass the majority of types available. They are force

10、 balanced, solid state (MEMS) and fluid filled. Within each category there are many variations, each having their own advantages and disadvantages. For example, the force balanced variety generally provides superior perf

11、ormance, but comes at a substantially higher cost. The MEMS based devices feature integral signal conditioning and relative ease of installation. However, thermal coefficients are extremely high, and significant compensa

12、tion is normally required to obtain acceptable accuracy in most applications.The fluid filled variety of tilt sensors comprises the largest industrial market sector by far. This is primarily due to the relative low cost

13、to performance ratio. Within this genre we find primarily electrolytic and capacitive technologies. While limited in terms of response time, the majority of applications are effectively static, rendering this attribute m

14、oot.Electrolytic Tilt SensorsThe most enduring of all tilt sensors to date is the electrolytic type. Pre-dating World War II, this sensors roots extend back to the Genesis of electronic tilt sensing. Spectron Glass and E

15、lectronics, who effectively pioneered this industry, developed many of the electrolytic tilt limitation can be overcome with an approach, which incorporates a second tilt sensor offset 90 degrees (in the sensitive axis)

16、to the first. This design successfully provides a full 360 degree sensing range, but requires a sophisticated multiplexing routine within the electronics to discern the correct angular position.For narrow angle range mea

17、surements of below +/-15 degrees, the geometry of the sensor changes dramatically. To maintain acceptable accuracy and sensitivity, the radius of the fluid cavity must greatly increase (see figure 3). Electrode alignment

18、 within the cavity also becomes extremely critical. This highly developed design produces the most accurate tilt sensors available on the market, with sub-arc second resolution. Furthermore, by altering the profile of th

19、e internal cavity, excellent results have been achieved in attenuating sensitivity to vibration, a typical problem with fluid filled devices.Dual Axis Tilt SensorsWhen dual axis (X and Y) tilt sensing is required, two se

20、ts of electrodes are required. The second set of electrodes must be accurately positioned, perpendicular (orthogonal) to the first set. Spectron has developed a dual axis tilt sensor platform, which is comprised of a cyl