# Azimuth movement, data preparation, azimuth movement order, obstacle avoidance, azimuth movement features by car.

Driving in azimuths is a way of maintaining the intended path (route) from one point (landmark) to another in known azimuths and distances. In general, azimuth motion is applied at night. And also in the forest, desert, tundra and in other conditions that make map orientation difficult.

## Azimuth movement, data preparation, azimuth movement order, obstacle avoidance, azimuth movement features by car.

The route map with clear landmarks on turns is marked on the map. The directional angle and length of each straight section of the route are measured. Directional angles are translated into magnetic azimuths, and distances are converted into pairs of steps if the azimuthal movement is on foot. Or in the speedometer while marching on cars. Data for movement in azimuth is drawn on the map. If there is no map on the way, then make a route diagram or table.

## Azimuth driving order.

At the initial (first) reference point, using the compass, the direction of movement to the second reference point is determined by azimuth. In this direction, they notice some remote landmark (auxiliary). And begin to move in azimuth. Having reached the intended landmark, the direction of movement to the next intermediate landmark is again outlined by compass. And so continue the movement until reaching the second landmark.

In the same order, but in a different azimuth, they continue to move in azimuth from the second landmark to the third, etc. On the way, taking into account the traveled distance, they look for landmarks on the turns of the route and thereby control the correctness of movement. To facilitate keeping the direction, you should use celestial bodies and various signs:

Straightness of a walking column or own track when skiing.
The direction of the ripples in the sand.
Zastrug in the snow.
Wind direction, etc..

By heavenly lights you can confidently withstand the direction of motion. Refining it by compass approximately every 15 minutes. The accuracy of the output to the landmark depends on the accuracy of determining the direction of movement and measuring the distance. Deviation from the route due to an error in determining the direction of the compass usually does not exceed 5% of the distance traveled. If the direction of movement is specified by the compass often enough, then the deviation from the route will be about 3% of the distance traveled.

## Azimuth obstacle avoidance.

If there are obstacles on the route, then bypass routes are marked on the map and the necessary data are prepared for this – azimuths and distances. Obstacles not taken into account when preparing data for traffic bypass one of the following methods.

## First way.

It is used when the obstacle is viewed to the end. In the direction of movement, a landmark is marked on the opposite side of the obstacle. Then they bypass the obstacle, find the observed landmark and from it continue to move in azimuth in the same direction. The obstacle width is estimated by eye and added to the distance traveled to the obstacle..

## Second way.

An obstacle, the opposite side of which is not visible, is circumvented in the directions forming a rectangle or parallelogram, the azimuths and lengths of the sides of which are determined on the ground. From point A go along the obstacle in the chosen direction. In our example, in azimuth 280 degrees.

## An example of avoiding an obstacle whose opposite side is not visible.

Passing to the end of the obstacle (to point B) and measuring the obtained distance (200 pairs of steps), continue to move along a given azimuth. In our example, in the azimuth of 45 degrees to point C. From point C, go to the main route in the inverse azimuth of direction AB. In our example, in the azimuth of 100 degrees, measuring 200 pairs of steps in this direction (the distance of the LED is equal to AB). Here, the length of the BC line is added to the distance traveled from point No. 2 to point A, and the movement continues to point No. 3.

## Features of movement in azimuths by car.

The direction of motion specified by the magnetic azimuth is determined by the compass, located no closer than 10 meters from the car and 30-40 meters from the tank. Noticing in this direction the remote (auxiliary) landmark, they drive the car towards him and count the distance to the turning landmark using the speedometer. The machine is stopped here, and these actions are repeated again..

When driving in azimuths by car, when there are no landmarks or they are not visible, you can use a compass. The use of the magnetic compass directly in the machine is very limited. The magnetic needle, under the influence of the magnetic field of the machine, deviates from the direction of the magnetic meridian. The magnitude of this deviation (compass deviation) is unstable and depends on the metal mass of the machine, its electromagnetic field, direction of motion and engine speed. Therefore, you can use the compass in the car only after preliminary determining its correction for a given direction of movement.

In practice, it is not the correction that is determined, but the calculation of the azimuth of the compass taking into account the correction. To do this, install the machine in a given direction, take a place in it as far as possible from the battery and measure the magnetic azimuth of the longitudinal axis of the machine with a compass. That is, the azimuth of the direction of motion.

Starting movement in azimuths, you need to make sure the stability of the magnetic needle. If it has a large oscillation amplitude, you should not use the compass in the car. When turning the route, all these steps must be repeated. That is, determine the compass correction for the new direction of travel.

Based on materials from the Handbook of Military Topography.
A. M. Govorukhin, A. M. Kuprin, A. N. Kovalenko, M. V. Gamezo.