Thermomechanical Deformation
Thermomechanical deformation effect arises when uneven temperature distribution across a structure causes localized differential expansion and internal stress. In high-precision sensor housings, thermal gradient strain distorts the physical geometry of the sensing elements, leading to bias drift and measurement errors. This mechanical distortion occurs when one side of a sensor component is heated by nearby electronics while the opposite side remains cool.
Physical Consequence
Unequal thermal expansion across the substrate bends the microscopic cantilever beams or warps the capacitive plates used in micro-machined sensors. This warping alters the rest gaps and spring constants of the structures, shifting the baseline signal without any external acceleration or rotation. These induced stresses often appear during rapid start-up cycles when internal heat distribution has not reached equilibrium.
Mitigation Technique
Designers employ materials with low coefficients of thermal expansion, such as fused silica or specialized alloys, to construct the critical mounting structures. Isolating power-dissipating electronics from the sensitive transducer elements further reduces the temperature differences across the chassis. Thermal symmetric layouts and copper heat planes are also incorporated to distribute energy evenly, minimizing the internal stress caused by localized hot spots.
Verification Method
Finite element models predict these deformation patterns before physical prototyping begins.
