质量特性工具

Onshape’s Measure and Mass properties tools allow designers to initiate critical design checks. The Measure tool is available in Part Studios and Assemblies. It is also available on drawings in a limited capacity.

Select one or more faces, edges, or vertices for a quick measurement without activating the Measure tool. Click Show measure details. Specify the Measurement type. When left at Show all, results for each measurement type are shown. For a specific type, set this to another option, such as Position, Radius, or Min distance. Specify the units of measurement for both Length and Angle. Change units at any time.

Select entities to measure in the graphics area. The results differ depending on the selections. If more than 2 items are selected, Onshape displays the total surface area and length of the selections. Selecting faces adds to the total surface area, while selecting edges adds to the total length. Selecting 2 lines identifies whether lines are parallel to each other. Several measurements are available: Parallel distance, Maximum distance, and Minimum distance. Each measurement also indicates the distances between the selections along the world axes. Selecting two fillet faces displays the dimension between their parallel axes, the total area, and the minimum and maximum distances.

Quickly create a driven or measured variable by clicking the variable icon beside any measurement, including quick measurements. The variable's value updates if the corresponding measurement changes. See mass properties calculations for faces and parts in Part Studio and Assembly tabs. Click Display mass and section properties. Click the Part tab for part calculations using the density of assigned materials. If no material is assigned, the instances are not used in the calculations.

The mass of each instance, the total mass of multiple instances, or the entire Assembly is calculated. Additionally, the Volume, Surface area, Center of mass, and Mass moments of inertia are determined. Click the Face tab to show face calculations. Select a face, including section view faces, or coplanar selection of faces. The results display the Surface area, Perimeter, and both Area and Polar moments of inertia. The results of mass property calculations are approximate. Depending on geometric complexity, the accuracy of the property calculations may vary. Enable Show calculation variance when necessary. Select any resultant value in the Measure tool or Mass properties to copy the value and use it elsewhere. Clicking the value once displays and selects the numerical value to its full precision or all decimal places. Clicking it again shortens the precision to match the Workspace units setting.