Understanding and calculating reaction forces in three dimensions is a fundamental task for engineers and designers. My 3D Free-Body-Diagram (FBD) Calculation Tool was developed to make this process intuitive, fast, and reliable — while maintaining full rigor of equilibrium equations in 3D.
Why Calculate Reaction Forces?
Every structural or mechanical system rests on supports that resist applied forces and moments. To ensure the structure is stable and that support capacities aren’t exceeded, you need to determine the exact reactions at each support point. This is especially challenging in 3D when multiple supports and load cases are involved.
About the Tool
The 3D FBD Tool calculates the reaction forces and moments on a rigid body subjected to external loads and moments. You simply define:
- The locations of the supports (in X, Y, Z coordinates)
- The applied forces (Fx, Fy, Fz) and moments (Mx, My, Mz)
- Constraints (equal stiffness, number of supports, etc.)
The tool solves the full system of equilibrium equations:
ΣFx = 0 ΣFy = 0 ΣFz = 0 ΣMx = 0 ΣMy = 0 ΣMz = 0
and outputs the reaction force components at each support in a clear, tabulated format. The results are balanced and exact (not approximate), ensuring confidence in your calculations.
Features
- Handles arbitrary support configurations in 3D space
- Supports multiple load combinations (forces and moments)
- Visualizes the Free Body Diagram for clarity
- Provides a reaction force table with totals
- Built for engineers who value accuracy and efficiency
How to Use It
- Open the tool: 3D Free Body Diagram Tool
- Input the support locations and external loads
- Click Calculate
- Review the reaction forces, moments, and totals
Conclusion
The 3D FBD Tool is designed to save time and reduce errors in structural calculations. It’s suitable for engineers, students, and anyone who needs to check or design support reactions quickly and with confidence.
Try it now: 3D Free Body Diagram Tool