# Model-Free Learning of Safe yet Effective Controllers

arXiv: https://arxiv.org/abs/2103.14600 · HTML: https://mlsanity.com/paper/2103.14600/

## Key facts

- Cited by 5 papers in the map (data through 14 Oct 2026).
- Builds on 21 of its 54 references that are in the map.
- First posted on arXiv 26 Mar 2021.

## Builds on (most cited first, 21 of 21)

- [Safe Reinforcement Learning via Shielding](https://mlsanity.com/paper/1708.08611/) (2017)
- [A Survey of Multi-Objective Sequential Decision-Making](https://mlsanity.com/paper/1402.0590/) (2014)
- [Reinforcement Learning With Temporal Logic Rewards](https://mlsanity.com/paper/1612.03471/) (2016)
- [On Learning Intrinsic Rewards for Policy Gradient Methods](https://mlsanity.com/paper/1804.06459/) (2018)
- [Reinforcement Learning for Temporal Logic Control Synthesis with Probabilistic Satisfaction Guarantees](https://mlsanity.com/paper/1909.05304/) (2019)
- [Omega-Regular Objectives in Model-Free Reinforcement Learning](https://mlsanity.com/paper/1810.00950/) (2018)
- [Control Synthesis from Linear Temporal Logic Specifications using Model-Free Reinforcement Learning](https://mlsanity.com/paper/1909.07299/) (2019)
- [Safe Multi-Agent Reinforcement Learning via Shielding](https://mlsanity.com/paper/2101.11196/) (2021)
- [Probably Approximately Correct MDP Learning and Control With Temporal Logic Constraints](https://mlsanity.com/paper/1404.7073/) (2014)
- [A Learning Based Approach to Control Synthesis of Markov Decision Processes for Linear Temporal Logic Specifications](https://mlsanity.com/paper/1409.5486/) (2014)
- [Verification of Markov Decision Processes using Learning Algorithms](https://mlsanity.com/paper/1402.2967/) (2014)
- [Reinforcement Learning with Probabilistic Guarantees for Autonomous Driving](https://mlsanity.com/paper/1904.07189/) (2019)
- [Multi-Agent Reinforcement Learning with Temporal Logic Specifications](https://mlsanity.com/paper/2102.00582/) (2021)
- [Temporal Logic Guided Safe Reinforcement Learning Using Control Barrier Functions](https://mlsanity.com/paper/1903.09885/) (2019)
- [Reinforcement Learning of Control Policy for Linear Temporal Logic Specifications Using Limit-Deterministic Generalized B"uchi Automata](https://mlsanity.com/paper/2001.04669/) (2020)
- [Learning-Based Mean-Payoff Optimization in an Unknown MDP under Omega-Regular Constraints](https://mlsanity.com/paper/1804.08924/) (2018)
- [Safe Reinforcement Learning via Probabilistic Shields](https://mlsanity.com/paper/1807.06096/) (2018)
- [Model-Free Reinforcement Learning for Stochastic Games with Linear Temporal Logic Objectives](https://mlsanity.com/paper/2010.01050/) (2020)
- [Probabilistically Guaranteed Satisfaction of Temporal Logic Constraints During Reinforcement Learning](https://mlsanity.com/paper/2102.10063/) (2021)
- [Synthesis of Discounted-Reward Optimal Policies for Markov Decision Processes Under Linear Temporal Logic Specifications](https://mlsanity.com/paper/2011.00632/) (2020)
- [Stochastic Games with Lexicographic Reachability-Safety Objectives](https://mlsanity.com/paper/2005.04018/) (2020)

## Built on by (most cited first, 5 of 5)

- [Omega-Regular Reward Machines](https://mlsanity.com/paper/2308.07469/) (2023)
- [Accelerated Learning with Linear Temporal Logic using Differentiable Simulation](https://mlsanity.com/paper/2506.01167/) (2025)
- [Omega-Regular Decision Processes](https://mlsanity.com/paper/2312.08602/) (2023)
- [Average Reward Reinforcement Learning for Omega-Regular and Mean-Payoff Objectives](https://mlsanity.com/paper/2505.15693/) (2025)
- [Reward Machines for Signal Temporal Logic](https://mlsanity.com/paper/2608.13625/) (2026)

## Abstract (arXiv)

We study the problem of learning safe control policies that are also effective; i.e., maximizing the probability of satisfying a linear temporal logic (LTL) specification of a task, and the discounted reward capturing the (classic) control performance. We consider unknown environments modeled as Markov decision processes. We propose a model-free reinforcement learning algorithm that learns a policy that first maximizes the probability of ensuring safety, then the probability of satisfying the given LTL specification and lastly, the sum of discounted Quality of Control rewards. Finally, we illustrate applicability of our RL-based approach.
