What does axonometric drawing mean?

Axonometric drawing is a kind of one-sided projection drawing, which can reflect the shapes of three coordinate planes of an object on one projection plane at the same time, close to people's visual habits, vivid, realistic and full of three-dimensional sense.

However, axonometric drawing generally can't reflect the real shape of each surface of an object, so it is poor in measurability and complicated in drawing. Therefore, axonometric drawings are often used as auxiliary drawings in engineering to illustrate the structure, installation and use of machines. In the design, axonometric drawing is used to help conceive and imagine the shape of the object, so as to make up for the deficiency of orthographic drawing.

basic feature

(1) The projections of two parallel lines remain parallel;

(2) The projection length of the line segment parallel to the coordinate axis is equal to the product of the axial expansion coefficient of the coordinate axis and the length of the line segment.

From the above properties, if the axial expansion coefficient is known, the length of each line segment parallel to the axonometric axis can be drawn in the axonometric drawing, which is the meaning of the word "axonometric" in the axonometric drawing.

Isometric diagram: the angles between axes are all 120 degrees; The axial expansion coefficient p=q=r =0.82 is 1.

Oblique axonometric drawing: the included angles between shafts are 90 degrees, 135 degrees, 135 degrees; Axial expansion coefficient p=r= 1 q=0.5.