Topology optimization for designing strain-gauge load cells

Abstract

Load cells are used extensively in engineering fields. This paper describes a novel structural optimization method for single-and multi-axis load cell structures. First, we briefly explain the topology optimization method that uses the solid isotropic material with penalization (SIMP) method. Next, we clarify the mechanical requirements and design specifications of the single-and multi-axis load cell structures, which are formulated as an objective function. In the case of multi-axis load cell structures, a methodology based on singular value decomposition is used. The sensitivities of the objective function with respect to the design variables are then formulated. On the basis of these formulations, an optimization algorithm is constructed using finite element methods and the method of moving asymptotes (MMA). Finally, we examine the

Topology optimization for worst load conditions based on the eigenvalue analysis of an aggregated linear system

“…Representing the mechanical aspects of the structure as a simple linear system can be effective in structural optimization when optimizing the fundamental structural characteristic of an uncertain input. The worst load case for uncertain loads was evaluated in this research, while the measurement error of the robotic load cells for uncertain measured loads was evaluated in our previous research [30]. In future research, we hope to extend the methodology to other structural optimization problems of systems with uncertain inputs, such as in the design of compliant mechanisms and multi-physics actuators with uncertain inputs.…”

“…Aggregation enables us to formulate the minimum required simple linear system for optimization to evaluate the relationship of target elements of the system even if the original problem is very large. In our previous work, minimization of the detection error of robotics load cells was performed based on this concept [30].…”

Use of a Novel Resistive Strain Sensor Approach in an Experimental and Theoretical Study Concerning Large Spherical Storage Tank Structure Behavior During Its Operational Life and Pressure Tests

“…As noted above, such tanks are critical equipment and it is important to test them for proper functioning, especially in the light of newer findings. For example, as reported in the paper, the stairs (which are not nationally or internationally regulated as constructive parts of large pressure vessels) may interfere with the proper functioning of the tanks.Most of the studies carried out in this field have focused on the pipe-type structures used with measurements performed by means of bidirectional tensor-resistive sensors [2,3], or studies carried out under laboratory conditions [4][5][6][7]. For example, Agbo et al presented a study [1] that describes investigations performed using tensor-resistive sensors regarding the behavior of some thin-walled metal structures with an operating usage history and subjected to an internal pressure.…”

“…As compared with his work (and other similar ones), in our case, considering the physical size of the structure discussed in this paper (diameter between 12,000-16,000 mm with wall thicknesses between 20-45 mm), applying the FEM and obtaining useful and verifiable results proved to be a real challenge. As a starting point, we used the optimization method for single-and multi-axis load cell structures developed by Takezawa et al [6], which was adapted to the complexity of the structures that were the subject of this study. This also led to the establishment of a new original problem-solving approach that implied the customization of the 3D modeling algorithm consisting of ten slice modules for large structures.The present study proposed a comparative study of the results obtained by applying the FEM and the results obtained following resistive strain sensor measurements during in situ overpressure tests.…”

Nonlinear Error Compensation for Load Cells Based on the Optimal Neural Network With an Augmented Lagrange Multiplier

“…This kind of hardware compensation method is simple but not a full-scale compensation. Takezawa et al [7] proposed a topology optimization method for designing strain gauge load cell and constructed an optimization algorithm using the finite-element method and the moving asymptotes method. This method can provide an optimal configuration of the load cell and decrease its nonlinear errors.…”