| Have you ever seen a land surveying team using | | | | they're measuring. To aid in accuracy, the |
| a camera-like devise on top of a tripod? Here's a | | | | reflector point has a leveling bubble on its top, so |
| quick explanation of that device, called a total | | | | that the person in charge of that end of the |
| station, and how it works. | | | | process can be sure the device is completely |
| A total station is a land-surveying tool used to | | | | level. |
| accurately measure distances, architecture and | | | | Leveling the reflector is extremely important to |
| geological land forms such as mountains. The | | | | ensure it matches the total station's height and |
| device is extremely accurate, with some able to | | | | gives an accurate distance reading that isn't |
| measure distances up to 0.1 millimeter or 1/1000 | | | | skewed to the left or right, up or down. |
| of a foot. Most surveyors don't need that much | | | | Some newer total stations, including the Topcon |
| accuracy (which necessitates a higher cost | | | | total station, offer reflectorless measuring devices. |
| out-of-pocket) and opt for a less expensive | | | | These pinpoint an object using a scope in a |
| model accurate to 1 millimeter or 1/100 of a foot. | | | | view-finder chosen by the surveyor using the |
| The total station itself looks a bit like a camera. | | | | device. The Topcon total station then emits a |
| You may have seen them mounted on a tripod -- | | | | modulated microwave or infrared signal that |
| they are often used at highway construction | | | | bounces off the target and back to the device, |
| zones to measure the distance of an expansion, | | | | allowing it to measure distances out to about 1.5 |
| new on-ramp or other change to the traffic | | | | miles (or 2 km). |
| pattern. The standard unit includes a second piece | | | | Total stations are finding uses beyond land |
| attached to a pole. | | | | surveying. Police departments have begun using |
| This second piece is the reflector, and it is usually | | | | the devices to precisely measure and record |
| manned by a second surveyor. Matching the | | | | elements of crime scenes. The data collected can |
| exact height of the total station relative to the | | | | offer a valuable record and even produce new |
| reflector is extremely important to ensure | | | | information about the crime scene when |
| accurate measurements, so often surveyors will | | | | processed through a computer. |
| do several trial runs before they note the points | | | | |