An inertial mass suspended from two or more clamped beams is a structure often used in MEMS accelerometers and other motion sensitive devices. A typical structure is as shown above. When an acceleration load is applied in the direction shown, the mass will undergo a displacement till the spring action of the beams balance out the acceleration load.
Use this form to calculate the displacement of the mass due to the acceleration load and the resulting stress in the beams. If there are more springs supporting the mass connected in parallel, the effective spring constant will be the sum of spring constants of all the beams.
The X-Y plot gives the distribution of stress on the beam surface. It shows that the stress changes from positive maximum to negative maximum along the length of the beam. When the mass is pushed down due to inertia, the surface stress near the clamped edge of the beam will be tensile and that near the mass will be compressive. The 2D and 3D surface plots show the deflection of the beam mass system under acceleration.