Highway measurement with GPS I do not know which of the base station settings and mobile station settings I are very vague, to the instrument to build a coordinate system how to build the relevant issues to me
For long tunnels, the conventional measurement of large bridges has the following limitations:1, long tunnels, bridges and other structures generally require the measurement level of four or more. With conventional measurement methods, often adopt the measure to increase the number of methods to extend the observation time, time consumption and labor consumption to try to improve the accuracy of.2, the long tunnel and bridge for the complex terrain region difficult, conventional control measure for visibility and network shape, often cut down the workload is quite large, so the measurement of the cost of a large, hard work.Link control network of high precision 3, long tunnel and bridge and low precision and route network, although with adjustment methods can be overcome, but because of the terrain conditions are difficult, the measurement workload to its connection, and is not too easy. In practical work, the control of the structure and the measurement of the route are often out of touch.
If you are a GPS base station location and measurement of road staff recommend that you use the professional version of the GPS version of the great error because you said is also a way of positioning is not accurate the coordinate system should also use professional equipment and operating personnel want to help you
Application of GPS in Highway SurveyHighway routes are generally in a ribbon corridor. It is often used in the plane control measurement, which includes the form of wire, closed wire, wire and so on. For important structures such as bridges, bridges, tunnels, etc., but also arranged into triangular network, linear lock and other forms.
Defects of conventional measurement methods:1, the specification of the length of the attached wire, the length of the wire and the length of the wire between the nodes have strict requirements, generally for high grade roads are required to meet the requirements of the first line. In this way, the length of the wire shall not be more than 10 km, or the length of the wire shall not exceed the length of the wire attached to the attachment of the wire length of 0.7 times. This requirement is generally difficult to achieve in the actual work, often appear super standardized operations.2, to collect the starting point for the general route of measurement and control is difficult to ensure the same measurement system, the measurement and measurement, often in the city of control points mixed together, the compatibility between systems, if the starting point is not compatible, is bound to affect the quality of measurement.3, serious damage to the national site, the impact of measurement operations. Due to the country's basic control points, mostly completed in 50s and 60s, after more than 30 years, some point due to the needs of economic construction is destroyed, and some people because of the lack of knowledge of human destruction. Route survey work in these areas, often in the 50 km above all can not find the wire control points. The quality of the route control survey is not guaranteed.4, ground visibility difficulties often affect the implementation of conventional measurement. The control points of the general route shall be located within 300 meters from the course. Due to visibility reasons, it is difficult to meet the conditions, even in a large range, and the dense shrub forest area, simply can not implement conventional control measure.
