Projected Curve in Solidworks

What is a Projected Curve?

A projected curve is a type of curve available in Solidworks which is used to create/project a curve onto the face of the model or to create a 3D curve in Solidworks. We can also create a 3D curve by creating two different sketches in two different planes, the intersection between the two sketches is converted as a Projected curve.

Application of Projected Curve : 

• A projected curve is used to create a curve onto the face/surface.
• It is used to create complex 3D curves with two different 2D sketches.
• Projected curves are mostly used in surface modeling. To create complex curves in the model.

Advantages of the Projected Curve :

• The projected curve is the replacement of the 3D sketch. 
• It makes the process easier to create complex 3D curves.
• Controlling the dimensions/curvature/shape is easier compared to controlling the nature of 3D sketches.

Comparison between a Projected curve and 3D sketch :

To create the 3D sketch, we don’t need any plan as a reference. The 3D sketch will be created in the working space without any reference. While creating the 3D sketch, we are able to move the points in all directions(X, Y & Z). But controlling the points and making the sketch a fully defined one without any reference is very hard in the 3D sketch.

In the case of the projected curve, we will be creating two different sketches in two different planes. The intersection between the two 2D sketches is converted as the projected curve. Controlling the dimensions and curvature of the projected curve is easy compared to the 3D sketch.

Types of Projection in the Projected Curve :

There are two types of projections available in the Projected curve. The differences and projections and it’s working are given below,

1.  Sketch on Face 
2.  Sketch on sketch

Sketch on Face :

Sketch on face is basically used to create a projected curve on the top of the face of the solid body or on top of the surface.

To create a projected curve by using sketch on sketch option, you need one sketch and one face/surface where the curve has to be created. You can refer to the below example for better understanding.

Fig 1 : Example for sketch on face type

    In the image given above the spiral is there in the bottom of the semi-sphere. If you want to project the spiral on the top surface of the semi-sphere sketch on face option is used.

    To project the spiral on top of the surface you need to follow the below steps.

• Open the projected curve command from Insert→ Curves→ Projected curves or go to the features tab under that select the projected curve option.
• Then, under the projection option select the sketch on face type. Then, it will show the property manager window to select the sketch and faces. Refer the below image for the property manager.

Fig 2 : Property manager and selections for a sketch on face type

•     In the sketch box, you need to select the sketch which has to be projected as a curve. In the face selection box, you have to select on which face the curve has to be projected. When you are selecting the face, the selected face becomes pink in color.
•     Under the face selection option, you can see there are two options available; these two options are used to change the direction for projections as per our requirements.
•     You can check in the below image; the spiral sketch is projected on the surface of the semi-sphere.

Fig 3 :  Resultant curve for sketch on face

Sketch on Sketch :

Sketch on sketch option is used to create a projected curve by using the two different sketches created in the two different planes. The intersection portion between the sketches is converted as a projected curve.

Sketch on sketch option is the most important type of projected curve. To create the complex surface models this option is used.

To understand about the projected curve consider the case given below, Consider in the solidworks there are three default planes (Front, Top & Right). If three default planes are available, there are eight quadrants available in the same. As of now the 2D sketch option which you have used to create sketches in the planes.

Fig 4 : Default planes and quadrants

Whenever we are creating the 2D sketches dependent upon the plane which we have selected, the dimension will change in XY,YZ or in ZX directions.

If you have to create a sketch in the quadrant there are two options available.

One is a 3D sketch and the other one is a Projected curve option. As we already discussed, controlling the dimension and curvature of the 3D sketch is very hard compared to the projected curve. 

In this case the projected curve is a really helpful tool for us. We will be creating the two different  sketches, the intersection between the sketches is converted as a projected curve.

To create a projected curve the sketches should satisfy the following parameters.

•     The sketch should have only one starting point and ending point. It can be made of different entities (Line,spline,Arc,etc,.) but it should have connectivity between each and every entity.
•     The sketch should intersect with one another. The sketch should be in two different planes. 
•     The Starting and ending point of the two sketches should be vertical or coincident with one another. (The sketches starting and ending points to be in the same place).

    Consider there are two different sketches created with the random dimensions in two different planes(Refer the image given below). The first sketch is created in the front plane and the second is created in the top plane.

Fig 5 : Sketches for projected curve

To create the projected curve, you need to follow the below steps.

• Open the projected curve command from Insert→ Curves→ Projected curves or go to the features tab under that select the projected curve option.
• Then, under the projection option select the sketch on sketch type. Then, select the two different sketches. It will show the preview of the projected curve yellow in color.

Fig 6 : Property manager and selection for sketch on sketch type

• To explain the intersection the sketches are extruded as surface to infinite length. You can see in the interaction portion of the surface is converted as projected.

Fig 7 : Resultant Projected curve with the surface extrude

 

Conclusion :

In this article, you have learned about the projected curve, the different types of the projected curve, and the concepts involved in creating the projected curve. After creating the projected curve by using the sketch on-sketch method, when you are looking at the projected curve normal to the plan with which you have created the sketch, the sketch and projected curve will be in the same place.