About the method of CAD positioning

It is very useful in AUTOCAD.

CAD graphic objects are usually drawn by specifying the position of the point or the input coordinate values.定位 CAD CAD2010's positioning function is extremely rich, you can input absolute coordinate value positioning, you can capture the precise positioning of object feature points, you can use orthogonal navigation, polar axis navigation, object tracking navigation positioning, you can also input relative coordinate values ​​for positioning … …. Among them, the method of inputting the relative coordinate value fixed point is more common and flexible. The following are several common methods precisely positioned relative to the point of how to locate the center of the figure describes an example:

FIG. (A)

1. Direct input from

Direct Distance Input Method: Specify the point by moving the cursor to indicate the direction and then entering the distance.

The direct distance input method is used in conjunction with polar axis navigation to draw straight lines of a specified length and angle. Its operation steps:

1) Start the LINE command and specify the first point;

2) Move the cursor until the navigation line with the same angle as the line to be drawn is displayed (premise: polar axis navigation Turn on, set the polar axis navigation angle to include the angle to be drawn).

3) At the command prompt, enter the distance. The direct distance input method can also be used in conjunction with object capture and object tracking to accurately locate points relative to the direction and distance specified by the object tracking point.

The positioning method of the center of the figure (1): 1) Start (specify the center of the circle, radius) to draw the circle command; 2) Move the cursor to the midpoint of L2 to pause, set the midpoint as the object tracking point 3) Move the cursor up the midpoint to indicate the direction; 4) Enter the distance 13, and the center of the circle can be correctly positioned.

2. TK Method

Tracking (command: tk): You can specify a series of temporary points, each of which is offset from the previous point. Figure (1) Positioning method of the center of the circle: Command: _circle Specify the center of the circle or [three points (3P) /two points (2P) /tangency, tangency, radius (T)]: tk //start the circle command Then, enter tk tracking, the first tracking point: //Click the red marker point as the first temporary tracking point. Next point (press ENTER to end the tracking): 20 //Move to the right of the first temporary tracking point Cursor, enter the offset distance 20, determine the next temporary tracking point, the next point (press ENTER to end the tracking): 13 //Move the cursor over the second temporary tracking point, enter the offset distance 13, and determine the third temporary Tracking point Next point (press ENTER to end tracking): //Press ENTER to end tracking. The point at the red marker point (@20,13) is selected as the center of the circle. Specify the radius of the circle or [Diameter (D)]: 6 //Enter the radius, press Enter to complete

3. FROM method

Use the command to locate the offset from the reference point. Create a reference point using “From” in the object capture menu, and then enter the relative coordinates for positioning. The positioning method of the center of the circle in Figure (1): 1) Start (specify the center of the circle, radius) to draw the circle command; 2) Start the From command modifier at the prompt of the circle center …” of the specified circle. There are three ways: a) Hold down the SHIFT key and click the right mouse button, click on the temporary “Object Capture” context menu and click “(F)& quoquo; b) Click on the “Object Capture” button. “ From & rdquo; object capture button c) At the command prompt, enter “ cut point & rdquo; object capture name from 3) At the command line & ldquo; base point: & rdquo; prompt, click the red mark point as the base point; 4 Enter the coordinates (x, y) of the center of the circle relative to the base point. In this example, 20, 13, complete the positioning of the center of the circle; 5) Enter the radius of the circle and draw the circle.

4. After moving to the current point to the reference point, enter the relative coordinates for positioning

Figure (1) Positioning method for the center of the circle: 1) Start (specify the center of the circle, radius) draw the circle command 2) Move the cursor to the red mark base point, click the left mouse button to confirm, and then press the ECS button to end the command. This step is to move the current point of the cursor to the base point position; 3) Directly enter (Enter) or press Spacebar (Backspace), start again (specify the center of the circle, radius) draw the circle command; 4) Enter the coordinates of the center of the circle relative to the base point (@x, y), in this case @20,13 5) Enter the radius of the circle to complete the circle draw.

5. Method of adding auxiliary line by offset command Positioning method of center point in diagram (1): 1) Start modification| The offset (PARALLEL) command shifts the line L1 to the left by 20 units. 2) The same method offsets the line L2 by 13 upwards. The intersection of the two auxiliary lines is the position of the center of the circle. 3) Restart (specify the center of the circle, radius) to draw a circle command, capture the intersection of the two auxiliary lines as the center point, and enter the radius to draw the circle.

After mastering a variety of precise point determination methods, you can choose the most suitable simple method according to different conditions, so that you can work comfortably and easily.