 # ACS Type

You can choose from these ACS types: Rectangular, Cylindrical, and Spherical.

## Rectangular

Points are specified like the design cube coordinate system, with coordinates expressed in the form (X,Y,Z). You can use AccuDraw to define, save, and retrieve rectangular ACSs. ## Cylindrical

Points are specified as two magnitudes (R and Z) and an angle (q), with coordinates expressed in the form (R, q, Z).

The process of locating a point in a cylindrical ACS can be thought of as follows:

1. Moving from the origin along the x-axis a distance of R.
2. Rotating about the z-axis at an angle of q.
3. Finally, moving parallel to the z-axis a distance of Z. ### Cylindrical ACS

Note: In 2D, there is no depth (z-axis), and cylindrical coordinates are commonly known as polar coordinates.

These are used to position a data point with a Cylindrical ACS:

• AX=R,q,Z for an exact location, where:

R is the distance from the origin, along the x-axis.

q is the angle counterclockwise from the x-axis about the z-axis.

Z is the distance in the z-direction.

• AD=ΔR,Δq,ΔZ for locations relative to a tentative point, where:

ΔR is the difference in distance from the origin, along the x-axis.

Δq is the difference in the angle counterclockwise from the x-axis.

ΔZ is the difference in the distance in the z-direction.

## Spherical

Points are specified by a magnitude (R) and two angles (q and f), with coordinates expressed in the form (R, q, f).

The process of locating a point in a spherical ACS can be thought of as follows:

1. Move from the origin along the x-axis a distance of R to establish a radius vector.
2. Rotate this vector about the z-axis at an angle of q.
3. The angle f is the angle between the radius vector and the positive z-axis. ### Spherical ACS

These key-ins are used to position a data point with a Spherical ACS:

• AX=R,q,f for an exact location, where:

R is the radius vector distance from the origin.

q is the angle counterclockwise from the x-axis about the z-axis.

f is the angle between the radius vector and the z-axis.

• AD=ΔR,Δq,Δf for locations relative to a tentative point, where:

ΔR is the difference in the radius vector distance from the origin.

Δq is the difference in the angle, counterclockwise, from the x-axis.

Δf is the difference in the angle between the radius vector and the z-axis.