October 14, 2011
Ever since version 0.8.0051 of Grasshopper, there is a second solver available from within Galapagos which implements the Simulated Annealing algorithm. Like the existing Evolutionary solver, Simulated Annealing is also a meta-heuristic technique, but works in a fundamentally different fashion. Having access to both solvers makes it easier to circumvent some of the shortcomings of each. Ironically, Simulated Annealing is a much simpler process than Simulated Evolution but may be harder to understand since the real-world analogy is more abstract and based on a less well known process.
In metallurgy, annealing is the process of controlled heating and cooling of metal to achieve certain material properties. At first, the metal is heated up to melting point so it can be cast or formed. At an atomic level, heat is nothing more than particle velocity. The particles (atoms & molecules alike) in a hot substrate move faster than the same particles in a cold substrate. At some point the velocity of two particles will be so high that they cannot succeed in forming a persistent bond between them. When this happens the substrate loses internal structure and turns liquid.