Fixed-Cost Simulation

Fixed-step, fixed-cost capability evaluation; solver selection; balancing speed and accuracy

The fixed-step solver type, step size, and number of iterations that you specify for a model affect the speed and accuracy of your real-time simulation. The fixed-cost simulation process helps you choose fixed-cost solver settings that allow your model to run on a target machine without generating overruns.

Functions

simscape.getLocalSolverFixedCostInfo Determine iteration requirement when transitioning to fixed cost (Since R2021b)

Topics

Fixed-Cost Simulation Process
Configure the solvers in your Simscape™ model for real-time simulation.
Fixed-Cost Simulation for Real-Time Viability
Avoid real-time simulation overruns by choosing a step size and number of iterations that limit the computational cost of simulating your Simscape model.
Estimate Computation Costs
Determine if your Simscape model is likely to cause an overrun when you simulate it on your real-time target machine by estimating computational costs.

Featured Examples

Determine System Stiffness

Choose the right solver for fixed-cost simulation based on the numerical stiffness of your model.

Reduce Numerical Stiffness

Eliminate components that cause rapid changes to reduce the computation cost of simulation and to make your Simscape model real-time capable.

Choose Step Size and Number of Iterations

Optimize your Simscape model for real-time simulation and avoid overruns by specifying a combination of step size and number of iterations that provides acceptable accuracy and speed.

Increase Simulation Speed Using the Partitioning Solver

Improve performance by using the Simscape Partitioning solver to convert a large system of equations into several smaller systems of equations that are easier to solve.

Reduce Computation Costs

Make your Simscape model real-time capable by identifying and eliminating unnecessary, computationally costly processes such as redundant monitoring and data logging.

Reduce Fast Dynamics

To make your Simscape model real-time capable, decrease computational cost by reducing fast dynamics that you identify using frequency-response and pole-speed analyses.