In this article we will consider a device such as a curvimeter. What is it - few know. And everything is quite simple. The word itself comes from the Latin curvus, which means a curve. And this device is intended for accurate measurement of distances on topographic maps, if the segment has a winding structure.
Curvimeter for cards. Mechanical design
This device was invented for a long time and is very simple in its design. In the above photo you can see old-style curvimeters. They are significantly different from modern electronic models. Most often, the mechanical version of the curvimeter looks like a small plastic device (no more than 50 grams) with a wheel located at one end, and comes with a case.
Existing types of curvimeters have either a circular or rectilinear scale. Regardless of this feature, they can be of only two types. Or it is a device with a fixed dial, in which case the arrow (index) will be movable. Or with a movable dial, but a fixed index. In order to measure the length of the desired segment, it is necessary to roll the wheel at the curvimeter along it. The standard scale length is 100 centimeters. There is of course a slight error in this device. It corresponds to 0.25 centimeters when measuring a line with a length of not less than 50 cm.
Some mechanical curvimeters have both a metric and an inch scale. The step of dividing the metric scale is one centimeter, inch - 0.05 inches.
Rules for using a curvimeter
Now let's talk about the rules that a curvimeter requires. What these rules are and why they are needed are described below.
Using a curvimeter for measurement, you provide the most accurate result, showing the length of the curved line on the map, without spending a lot of time and effort. But do not forget that when working with the curvimeter, it is necessary to observe some rules that can reduce the error.
First: do not try to measure the entire length of the required length at once. The best option would be to divide the entire line into small sections. In order not to get confused, you need to measure from one noticeable landmark to another. This is necessary in order to increase the accuracy of the result.
The second rule provides for the use of large-scale maps. The bigger, the better. The most optimal cards are 1:50 000 and 1: 100 000. The accuracy will be higher if you are not too lazy to carefully draw a curvimeter along all existing bends of the line.
The third rule applies not only to working with a curvimeter. The more times you measure the required segment, the less chance of error. It should be noted that the electronic curvimeter is more accurate than a conventional mechanical one.
Varieties of curvimeters and their advantages
As noted above, one of the oldest and most traditional designs is a mechanical curvimeter. The difference between different types and manufacturers is only in the type of scale and the display of results. More modern models of curvimeters can be made, for example, in the form of a keychain and equipped with additional functions. It can be a built-in compass or something else.
The advantages of mechanics include a simple device and use, the operation of such devices does not depend on the effects of weather and climate. As well as independence from the power source, shock resistance and resistance to moisture.
Electronic curvimeter
The electronic device of the curvimeter differs from the previous version in higher cost and more complex construction. Very often, manufacturers of these devices try to give them a ton of all sorts of additional functions, which is not always necessary. For example, there are models equipped in addition to the main task also with a flashlight, calculator, compass. And there are electronic models made in the form of a conventional pen.
More complex designs are intended for a variety of difficult to perform graphical measurements, as well as calculations. They are equipped with software, have a connection to a computer and have a large number of functions of an architectural and engineering nature. The capabilities of such a device include processing various values (up to 50), such as feet, inches, and so on, and, of course, a metric scale. Such a curvimeter can be used when working with drawings and maps of any complexity. Another positive feature of this model is data storage.
The disadvantages of the electronic version of the curvimeter include sensitivity to weather influences and dependence on the power source. Impact resistance is also significantly lower. Most often, these electronic curvimeters are used when working in the office, but not in the field.
Travel curvimeter is another type of measuring device
Another curvimeter. What is it, and how does it differ from previous models?
Its other name is a measuring or road wheel. This view is also intended for marking and measuring distance, but not on the map, but on the terrain, most often with an uneven surface. It is used in cases where it is not possible to use light-range finders, tape measures and other devices.
Functions and principle of the road wheel
All types of measuring wheels have one operating principle. The difference is only in size, type of wheel (there are disc or with knitting needles), range, pitch, division of the counter (on the handle or wheel). And one more thing: they are also divided into two main types - electronic and analog. Most often, any of these curvimeters is equipped with a folding handle, a brake button and an accurate counter.
What functions are inherent in them? This measurement is forward and backward, as well as holding and zeroing.
Complete with such a travel curvimeter, there is a soft cover for easy carrying. The weight of this measuring device can vary from 1 to 1.5 kilograms.
Well, now you know enough about such a device as a curvimeter. What it is, what it is intended for, how it works, its types and advantages, but whether it is necessary or not, decide for yourself.