SolidWorks Center of Mass and Materials Tips

[mplanchard]

Center of Mass
Keeping your center of mass low to the base of the robot and between the wheels is good design practice to prevent the robot from tipping over. In SolidWorks 2013 you can display the center of mass in a part, assembly and drawing. You can also dimension to the center of mass in the drawing. Display the center of mass early in the assembly and create an assembly drawing early in your design process. As you add components to your assembly, the center of mass will update and the assembly drawing will update.

Click Insert, Reference Geometry, Center of Mass to display the symbol. Click Hide/Show in the Heads up view toolbar (icon looks like eye glasses in top graphics window row of icons) to show or hide the Center of Mass.

Assembly Visualization
Keeping weight down is a challenge. Use the SolidWorks Assembly Visualization tool to list components from highest to lowest mass. This is a quick way to see what components that are causing the biggest issues.

Materials
Don’t know the mass of your parts? No problem. Set the Material Properties in the Part Feature Manager. Right-click Materials folder in the FeatureManager. Click Edit Material. Right-click Materials. Click Manager Favorites. Add the common materials you are using such as 6061 Aluminum. Unless you are in Germany, don’t select the first folder DIN. Most of what you need for FRC is under SolidWorks Materials folder.

Override Mass Properties
Don’t know the material of your part or using imported geometry – no problem. Get a physical scale and weigh. From the weight, you can calculate mass. To insert the mass value into a part of an assembly, click the Evaluate tab. Click Mass Properties. Click the Override Mass Properties button. You can also override Center of Mass and Moment of Inertia.

Manage the Nuts and Bolts in an Assembly
All the nuts and bolts in a robot add up on the scales – but you don’t need them to be displayed all the time. SolidWorks Toolbox inserts the material and the mass custom property. Place your Nuts in Bolts into a folder and then suppress the folder when not required.
Right-click in a part in your assembly FeatureManager. Click Add to New Folder. Drag all the nuts, bolts and other hardware into the folder. Folders just help organize life. Marie