The Live Parts growth process consists of multiple stages: pre-target growth and post-target growth. During the pre-target growth phase, the initial Seed Cells grow and spawn new cells in the direction of their pre-defined end location, forming a stem. This stem encounters simulated simulated gravity forces in the Live Part environment. When these gravity forces cause the stem to experience strain and deform, Live Parts triggers additional cell growth in the free directions where there are no cells in order to strengthen the stem. Without gravity forces during the pre-target phase, the stem will grow long and thin due to lack of strain, and are prone to being killed off.
By default, the Live Parts for SOLIDWORKS Add-in has expression values for oscillating gravity waves in the X and Z directions and a constant negative (downward) value for gravity forces in the Y direction.
Defining Gravity Forces in SOLIDWORKS:
- Select Settings in the Live Parts for SOLIDWORKS Add-in Toolbar.
- Adjust the "Pre Target Gravity Forces" and/or the "Post Target Gravity Forces". You can input constant values or define these as expressions varying over time.
- Select Save.
Users can also adjust the gravity forces in real-time during the Live Parts growth process by taking any of the following actions:
- Click and drag the Gravity Multiplier slider bar in the Advanced Controls Window to simply multiply the gravity forces defined using the SOLIDWORKS Add-in and imported into Live Parts.
- Click and drag the Gravity X/Y/Z slider bars in the Advanced Controls Window to individually adjust the X/Y/Z components of the gravity forces. This action automatically checks the Override Gravity option above the sliders, and sets the value of the each component to the static value in the slider bar.
- CTRL + Left Click on the Gravity X/Y/Z sliders in the Advanced Controls Window to edit the expression value for dynamic gravity forces if they are pre-defined as expressions using the SOLIDWORKS Add-in.
By unchecking Override Gravity, the gravity forces revert to those pre-defined using the SOLIDWORKS Add-in.
Please visit this article for more information on modifying forces in real-time.
Notes on Gravity Forces:
- In Live Parts, it is generally good practice to have a strong and constant gravitational force in one direction and to define oscillating gravity waves in the other two directions.
- This simulates the way wind blows on tree branches, causing them to have resilience to unexpected forces.
- As an example: if you are growing a symmetrical wheel standing upright with the main axis in the Z direction, you should align the constant gravity force in the Z direction and oscillating gravity waves in the X and Y directions. This way the wheel would experience forces aligned with the symmetry of the part.