# DAMPER: Return-Prioritized Gradient Control for Smooth Policies

arXiv: https://arxiv.org/abs/2609.38903 · HTML: https://mlsanity.com/paper/2609.38903/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Placed in RL theory and sample complexity, one of 15 directions in Deep reinforcement learning methods.
- Builds on 21 of its 28 references that are in the map.
- First posted on arXiv 30 Sep 2026.

## Placed in

- Deep reinforcement learning methods / [RL theory and sample complexity](https://mlsanity.com/deeprl/rl-theory-and-sample-complexity/)

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

- [Soft Actor-Critic: Off-Policy Maximum Entropy Deep Reinforcement Learning with a Stochastic Actor](https://mlsanity.com/paper/1801.01290/) (2018)
- [Addressing Function Approximation Error in Actor-Critic Methods](https://mlsanity.com/paper/1802.09477/) (2018)
- [Gradient Surgery for Multi-Task Learning](https://mlsanity.com/paper/2001.06782/) (2020)
- [GradNorm: Gradient Normalization for Adaptive Loss Balancing in Deep Multitask Networks](https://mlsanity.com/paper/1711.02257/) (2017)
- [Multi-Task Learning as Multi-Objective Optimization](https://mlsanity.com/paper/1810.04650/) (2018)
- [Conflict-Averse Gradient Descent for Multi-task Learning](https://mlsanity.com/paper/2110.14048/) (2021)
- [Adapting Auxiliary Losses Using Gradient Similarity](https://mlsanity.com/paper/1812.02224/) (2018)
- [Regularizing Action Policies for Smooth Control with Reinforcement Learning](https://mlsanity.com/paper/2012.06644/) (2020)
- [Smooth Exploration for Robotic Reinforcement Learning](https://mlsanity.com/paper/2005.05719/) (2020)
- [MetaBalance: Improving Multi-Task Recommendations via Adapting Gradient Magnitudes of Auxiliary Tasks](https://mlsanity.com/paper/2203.06801/) (2022)
- [L2C2: Locally Lipschitz Continuous Constraint towards Stable and Smooth Reinforcement Learning](https://mlsanity.com/paper/2202.07152/) (2022)
- [Learning from Simulation, Racing in Reality](https://mlsanity.com/paper/2011.13332/) (2020)
- [Gradient-based Regularization for Action Smoothness in Robotic Control with Reinforcement Learning](https://mlsanity.com/paper/2407.04315/) (2024)
- [Benchmarking Smoothness and Reducing High-Frequency Oscillations in Continuous Control Policies](https://mlsanity.com/paper/2410.16632/) (2024)
- [Careful with that Scalpel: Improving Gradient Surgery with an EMA](https://mlsanity.com/paper/2402.02998/) (2024)
- [Non-conflicting Energy Minimization in Reinforcement Learning based Robot Control](https://mlsanity.com/paper/2509.01765/) (2025)
- [Scalable Multi-Objective Robot Reinforcement Learning through Gradient Conflict Resolution](https://mlsanity.com/paper/2509.14816/) (2025)
- [Enhancing Control Policy Smoothness by Aligning Actions with Predictions from Preceding States](https://mlsanity.com/paper/2601.18479/) (2026)
- [Fair Cooperation in Mixed-Motive Games via Conflict-Aware Gradient Adjustment](https://mlsanity.com/paper/2508.17696/) (2025)
- [LPPG-RL: Lexicographically Projected Policy Gradient Reinforcement Learning with Subproblem Exploration](https://mlsanity.com/paper/2511.08339/) (2025)
- [Stabilizing the Q-Gradient Field for Policy Smoothness in Actor-Critic Methods](https://mlsanity.com/paper/2601.22970/) (2026)

## Abstract (arXiv)

Actor-critic methods achieve strong performance in continuous control, but their policies can produce highly oscillatory actions. A common remedy is to add auxiliary smoothness losses. However, their contribution can be negligible when their gradients are small relative to the native actor gradient. Moreover, existing methods often combine multiple auxiliary losses, complicating loss balancing without necessarily improving the return-smoothness trade-off. We introduce DAMPER (Direction-Aware Magnitude-Controlled Projection with Explicit Return Priority), which combines the native actor gradient with a temporal-consistency gradient through conflict-conditioned projection and adaptive magnitude control. It removes the auxiliary component opposing the actor gradient and scales the retained temporal direction relative to the actor gradient norm, preserving positive alignment with the native actor gradient. Experiments with TD3 and SAC on six continuous-control tasks show reduced action oscillation relative to the native agents in all 12 task-backbone pairs and the best oscillation score among the compared methods in eight, with task-dependent return trade-offs.
