To control orientation, which features are used?

• A. Parallelism, Perpendicularity, and Angularity
• B. Concentricity, Positioning, and Direction
• C. Shape, Form, and Size
• D. Length, Width, and Height

Answer: (A)

To control orientation in Geometric Dimensioning and Tolerancing (GD&T), the features that are utilized are parallelism, perpendicularity, and angularity. These controls focus on how one feature is aligned with respect to another feature.

Parallelism ensures that two features remain the same distance apart over their entire length, helping maintain a consistent orientation relative to each other. Perpendicularity specifies that a feature must be at a right angle to another feature, ensuring correct orientation in three-dimensional space. Angularity adds a specific angle that one feature must maintain in relation to another, providing precise control over the orientation of parts, especially in assemblies where precision is crucial.

The other options include features that serve different purposes in GD&T. Concentricity and positioning deal more with the location and alignment of features rather than pure orientation. Shape, form, and size are related to the overall geometry and dimensions of the part, while length, width, and height refer to basic dimensional measurements rather than controlling the orientation of features. All of this highlights why the focus on parallelism, perpendicularity, and angularity is essential for controlling orientation accurately in design and manufacturing processes.