Or the creation of special surfaces without using the unpredictable freeform surfacing tool: Take for example, customized spring design: For example, starting with a baseline equation for a trumpet bell, the curve can be revolved into a solid with parameters easily modified:ģD equation driven curves are also possible in SOLIDWORKS with the addition of a “Z” coordinate. Parametric curves can be used to create various solids. Please keep this in mind when working with parametric equation types. However, because t 1 and t 2 represent the start and end points of a spline, they can never coexist at the same location. Louis Gateway Arch was designed based on the Catenary function using cosh(x).įor 2D sketches, SOLIDWORKS allows the input of parametric equation types. cosh(x), sinh(x), etc.) however, these can be re-written in terms of e x such as: cosh(x) = (e x + e -x)/2. There are also no commands for hyperbolic trig functions (e.g. Imaginary and complex numbers are not included in this command. If the syntax happens to be wrong, the equation will highlight as a red color. Also keep in mind, negative exponents must be enclosed in parentheses. This means proper placement of parentheses is crucial in getting correct results. For example, sec(x) is asymptotic and only works over specific ranges such as -1.5 < x < 1.5 or 1.6 < x < 4.6 etc.Īs with any numerical input, order-of-operations applies.
Watch out when defining the range of inputs for “x” as some functions are undefined in certain regions. The following is a list of available mathematical functions in SOLIDWORKS Equation Driven Curves: Once an equation curve is generated, it can be positioned and integrated into a design as desired. Notice that the x-axis is interpreted as length instead of radians or degrees in this case. The curve is generated and referenced from the origin (0,0). In this example of a sine-curve, leaving the Equation Type on “Explicit,” we can see the y x field takes the equation in terms of “x” while x 1 and x 2 establish the range of values evaluated for “x” in the equation. To access 3-D curves, start a 3-D sketch and then choose Equation Driven Curve – otherwise it defaults to the 2-D setting in regular sketch mode. The command can be applied in both 2-D and 3-D space. 1/X where X = 0).Įquation Driven Curves can be found in sketch entities under “ Splines”: Also, because SOLIDWORKS evaluates functions and equations numerically, the command will not work for numbers or ranges that produce undefined outputs (e.g. The first thing to keep in mind using this command is that it actually generates a spline, and so certain limitations will apply which I’ll discuss a little later. This should not be confused with the Equations table where Global Variables are dealt with. To create these special kinds of curves, the best approach would be to utilize the Equation Driven Curves command. Examples of this might be the curvature of a lens, the design of a custom spring, wind-foil, or perhaps a roller-coaster path. Most SOLIDWORKS users are comfortable creating models with the familiar sketch commands (lines, rectangles, splines, arcs, etc.) however, there are occasions when a design is dependent on mathematical functions or equations to describe its geometry/topology. Selecting “Tangent to curve” will rotate the instances ever so slightly to match the curve.Magic of SOLIDWORKS Equation Driven Curves Not only do I want to place the instances along this curve, I want to orient the instances with respect to the curve. If you consider what we’re after, we’re not following the curved edge, per se, but we are following the offset of that curved edge. I want to keep the instances equally distributed throughout the curve, so I check the “Equal Spacing” option. Set the number of instances and the spacing if required. The first box is asking for the curve to follow, so select the converted curve. Drag the endpoints to resize the curve (remember the patterns go right to the endpoints). In order to get that geometry, start a sketch, and use the “convert entities” command to create that arc. Curve Driven Patterns like to follow the curve exactly, right to the end points. However, we need an extra bit of information before we can launch the command. For patterns that require following a path, Curve Driven Pattern is the way to go. The plan is to pattern this all along the curved edge following the edge.