Geometric Constraints Flashcards

What is the key difference between geometric constraints and dimensional constraints in CAD?

Answer: Geometric constraints define shape relationships; dimensional constraints define size and position numerically

Geometric constraints define qualitative relationships (parallel, perpendicular, tangent), while dimensional constraints assign numeric values for size and position.

What does an 'Equal' constraint do when applied to two lines?

Answer: Makes them the same length

An Equal constraint forces two lines (or curves) to maintain identical lengths, so changing one automatically updates the other.

Which constraint ensures a point lies exactly on a curve or line (not necessarily at its endpoint)?

Answer: On Curve (Point On)

A 'Point On' or 'On Curve' constraint forces a point to lie anywhere along a line, arc, or spline rather than requiring it to match an endpoint.

What is 'over-constraining' in CAD sketching?

Answer: Applying redundant or conflicting constraints that make the sketch mathematically unsolvable or over-defined

Over-constraining occurs when constraints conflict or are redundant, leaving no degree of freedom and making the sketch over-defined — most CAD tools highlight this as an error.

Which geometric constraint makes two lines or curves meet at a 90-degree angle?

Answer: Perpendicular

A Perpendicular constraint forces two lines (or a line and a curve) to intersect at exactly 90 degrees.

What does a 'Midpoint' constraint do in a CAD sketch?

Answer: Forces a point to lie at the exact center of a line or arc

A Midpoint constraint anchors a point (such as another line's endpoint) to the exact middle of a selected line or arc.

In most CAD applications, what color are sketch elements typically displayed in when they are 'fully constrained'?

Answer: Black or dark gray

Most CAD systems (SolidWorks, CATIA, Inventor) display fully constrained sketch geometry in black or dark gray, indicating no remaining degrees of freedom.