Optimization Objectives
The Optimization Objective is what property, or ‘Design Response,’ we hope to minimize or maximize within our part. nTop supports several design responses, including Structural Compliance, Volume Fraction, Displacement, Stress, and Natural Frequency. Use the Optimization Objective block to specify the design response(s). Below, the Objective is to minimize structural compliance.
Most optimization objectives aim to minimize the part’s Structural Compliance (maximizing the stiffness). You may choose a different response (E.g., Stress, Displacement). However, remember that this solution will take longer to converge since a static structural analysis is conducted at each iteration (assigning new density and sensitivity values for each element).
Multiple Objectives
In Topology Optimization, you can apply multiple objectives by populating the Design Response List in your Optimization Objective block with more than one design response.
We can use multiple Objectives to consider the response of a part to several different loading cases it may experience. We can also use multiple Objectives to balance an optimization based on displacement response and compliance, for example. The various Boundary Condition Lists must share the same Displacement Restraint (‘Fix’) block. The importance of each Objective can be given a weighting factor using the Weights input based on the following equation (the weighting factors are not normalized). If the Weighting input is blank, the multiple objectives will be weighted equally.
w = w1 * f1 +w2 * f2 + … + wn *fn
