CMA-ES for Safe Optimization
Abstract: In several real-world applications in medical and control engineering, there are unsafe solutions whose evaluations involve inherent risk. This optimization setting is known as safe optimization and formulated as a specialized type of constrained optimization problem with constraints for safety functions. Safe optimization requires performing efficient optimization without evaluating unsafe solutions. A few studies have proposed the optimization methods for safe optimization based on Bayesian optimization and the evolutionary algorithm. However, Bayesian optimization-based methods often struggle to achieve superior solutions, and the evolutionary algorithm-based method fails to effectively reduce unsafe evaluations. This study focuses on CMA-ES as an efficient evolutionary algorithm and proposes an optimization method termed safe CMA-ES. The safe CMA-ES is designed to achieve both safety and efficiency in safe optimization. The safe CMA-ES estimates the Lipschitz constants of safety functions transformed with the distribution parameters using the maximum norm of the gradient in Gaussian process regression. Subsequently, the safe CMA-ES projects the samples to the nearest point in the safe region constructed with the estimated Lipschitz constants. The numerical simulation using the benchmark functions shows that the safe CMA-ES successfully performs optimization, suppressing the unsafe evaluations, while the existing methods struggle to significantly reduce the unsafe evaluations.
- Augmented Lagrangian Constraint Handling for CMA-ES — Case of a Single Linear Constraint. In Parallel Problem Solving from Nature – PPSN XIV. Springer International Publishing, Cham, 181–191.
- Bayesian optimization with safety constraints: safe and automatic parameter tuning in robotics. Machine Learning 112, 10 (2023), 3713–3747. https://doi.org/10.1007/s10994-021-06019-1
- Safe controller optimization for quadrotors with Gaussian processes. In 2016 IEEE International Conference on Robotics and Automation (ICRA). 491–496. https://doi.org/10.1109/ICRA.2016.7487170
- Constrained Bayesian Optimization with Particle Swarms for Safe Adaptive Controller Tuning. IFAC-PapersOnLine 50, 1 (2017), 11800–11807. https://doi.org/10.1016/j.ifacol.2017.08.1991 20th IFAC World Congress.
- GPyTorch: Blackbox Matrix-Matrix Gaussian Process Inference with GPU Acceleration. In Advances in Neural Information Processing Systems.
- Batch Bayesian Optimization via Local Penalization. In Proceedings of the 19th International Conference on Artificial Intelligence and Statistics, Vol. 51. PMLR, 648–657.
- Nikolaus Hansen. 2016. The CMA Evolution Strategy: A Tutorial. CoRR abs/1604.00772 (2016). arXiv:1604.00772
- CMA-ES/pycma on Github.
- Nikolaus Hansen and Anne Auger. 2014. Principled Design of Continuous Stochastic Search: From Theory to Practice. Springer Berlin Heidelberg, Berlin, Heidelberg, 145–180. https://doi.org/10.1007/978-3-642-33206-7_8
- Nikolaus Hansen and Andreas Ostermeier. 1996. Adapting arbitrary normal mutation distributions in evolution strategies: The covariance matrix adaptation. In Proceedings of IEEE International Conference on Evolutionary Computation. 312–317. https://doi.org/10.1109/ICEC.1996.542381
- Array programming with NumPy. Nature 585, 7825 (2020), 357–362. https://doi.org/10.1038/s41586-020-2649-2
- An evaluation of sequential model-based optimization for expensive blackbox functions. In Proceedings of the 15th Annual Conference Companion on Genetic and Evolutionary Computation. Association for Computing Machinery, New York, NY, USA, 1209–1216. https://doi.org/10.1145/2464576.2501592
- Avoidance of constraint violation for experiment-based evolutionary multi-objective optimization. In 2009 IEEE Congress on Evolutionary Computation. 2756–2763. https://doi.org/10.1109/CEC.2009.4983288
- Are Evolutionary Algorithms Safe Optimizers?. In Proceedings of the Genetic and Evolutionary Computation Conference. Association for Computing Machinery, 814–822. https://doi.org/10.1145/3512290.3528818
- Safe Learning and Optimization Techniques: Towards a Survey of the State of the Art. In Trustworthy AI - Integrating Learning, Optimization and Reasoning. Springer International Publishing, Cham, 123–139.
- Dong C Liu and Jorge Nocedal. 1989. On the limited memory BFGS method for large scale optimization. Mathematical Programming 45, 1 (1989), 503–528. https://doi.org/10.1007/BF01589116
- Safe Reinforcement Learning for Automatic Insulin Delivery in Type I Diabetes. In Reinforcement Learning for Real Life Workshop, NeurIPS 2022.
- Learning soft task priorities for safe control of humanoid robots with constrained stochastic optimization. In 2016 IEEE-RAS 16th International Conference on Humanoid Robots (Humanoids). 101–108. https://doi.org/10.1109/HUMANOIDS.2016.7803261
- Masahiro Nomura and Masashi Shibata. 2024. cmaes : A Simple yet Practical Python Library for CMA-ES. arXiv preprint arXiv:2402.01373 (2024).
- Gaussian Processes for Machine Learning. Vol. 1. Springer.
- Moncef Gabbouj Serkan Kiranyaz, Turker Ince. 2014. Multidimensional Particle Swarm Optimization for Machine Learning and Pattern Recognition (first ed.). Springer. https://doi.org/10.1007/978-3-642-37846-1
- Safe Exploration for Optimization with Gaussian Processes. In Proceedings of the 32nd International Conference on Machine Learning (Proceedings of Machine Learning Research, Vol. 37). PMLR, 997–1005.
- Lauchlan Toal and Dirk V. Arnold. 2020. Simple Surrogate Model Assisted Optimization with Covariance Matrix Adaptation. In Parallel Problem Solving from Nature – PPSN XVI. Springer International Publishing, 184–197.
- SciPy 1.0: Fundamental Algorithms for Scientific Computing in Python. Nature Methods 17 (2020), 261–272. https://doi.org/10.1038/s41592-019-0686-2
- Surrogate-Assisted (1+1)-CMA-ES with Switching Mechanism of Utility Functions. In Applications of Evolutionary Computation. Springer Nature Switzerland, 798–814.
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