Geometric Constructions and Experiments

Line to Point

The dark red arc is being constructed.

Drag the small black dots to see the construction features change interactively.

Construction lines are shown visually as line segments even when used as lines or rays.

Line to Line

The dark red arc is being constructed.

Drag the small black dots to see the construction features change interactively.

Construction lines are shown visually as line segments even when used as lines or rays.

Line to Circle

The dark red arc is being constructed.

Drag the small black dots to see the construction features change interactively. The circle will maintain its radius when the center point is dragged.

Construction lines are shown visually as line segments even when used as lines or rays.

Cam Lobe

The dark red nose circle and dark red flank arc are being constructed.

Drag the small black dots to see the construction features change interactively. Edit the data to see the drawing use the specified values.

The base circle will maintain its radius when the center point is dragged.

Construction lines are shown visually as line segments even when used as lines or rays.

Cam Lobe Data






Bezier Cam

The cam is being defined by the Bezier curves in the cam profile graph (below the cam).

Drag the small blue and black dots to see the Bezier curves of the cam profile change shape. The cam above it is automatically drawn to match the cam profile.

Chord to Radius

The dark red arc is being constructed.

Compute an arc radius given a chord and the distance from the chord to the arc.

Drag the small black dots to see the construction features change interactively.

Construction lines are shown visually as line segments even when used as lines or rays.

Circle Intersection

The two red dots are being calculated.

Drag the small black dots to see the construction features change interactively.

Construction lines are shown visually as line segments even when used as lines or rays.

Circle Tangent

The dark red tangent line is being calculated.

Drag the small black dots to see the construction features change interactively.

Construction lines are shown visually as line segments even when used as lines or rays.

Curved Circle Tangent

The dark red tangent curve is being calculated. The tangent radius is a fixed amount in this construction.

Drag the small black dots to see the construction features change interactively.

Construction lines are shown visually as line segments even when used as lines or rays.

Running Cam Follower Simulation

The red lines and red circle are being computed. The cam is being drawn based on a set of measurements.

This is an active simulation and doesn't have interactive elements. The cam follower is simulated by checking for intersections of the follower circle and the various arcs of the cam.

Slow Bezier Drawing

Lines between the control points are used to find the points along the lines that are always proportional to the distance along the curve of the point being calculated. The yellow dots are calculated first and then used to calculate the positions of the red dots. The final dark red dot is calculated using the line between the light red dots.

The green line connects the black dot to the closest point along the curve.

Drag the small black dots to see the construction features change interactively.

Arc on Lines

The dark red arc is calculated using the two black lines. The black line that is not long enough to reach the arc, is extended in red.

Incorrect results are generated for parallel and crossing lines, as well as a few other configurations.

Drag the small black dots to see the construction features change interactively.

Geneva Mechanism

The gray circle on the left is the input disk with the small circle on it's radius being the "pin". The black circle on the right is the slotted circle with the green lines being the slots.

The anti-slip parts of the mechanism are not drawn since they don't affect the simulation. Those parts would keep the output from turning when a pin is not in a slot.


Some combinations won't work here or in real life: 6:4+,5:4+,4:5+,3:7+

Show Construction Step
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