AffordDP : Generalizable Diffusion Policy
with Transferable Affordance

Abstract

Diffusion-based policies have shown impressive performance in robotic manipulation tasks while struggling with out-of-domain distributions. Recent efforts attempted to enhance generalization by improving the visual feature encoding for diffusion policy. However, their generalization is typically limited to the same category with similar appearances.

Our key insight is that leveraging affordances—manipulation priors that define "where" and "how" an agent interacts with an object—can substantially enhance generalization to entirely unseen object instances and categories. We introduce the Diffusion Policy with transferable Affordance (AffordDP), designed for generalizable manipulation across novel categories. AffordDP models affordances through 3D contact points and post-contact trajectories, capturing the essential static and dynamic information for complex tasks. The transferable affordance from in-domain data to unseen objects is achieved by estimating a 6D transformation matrix using foundational vision models and point cloud registration techniques. More importantly, we incorporate affordance guidance during diffusion sampling that can refine action sequence generation. This guidance directs the generated action to gradually move towards the desired manipulation for unseen objects while keeping the generated action within the manifold of action space. Experimental results from both simulated and real-world environments demonstrate that AffordDP consistently outperforms previous diffusion-based methods, successfully generalizing to unseen instances and categories where others fail.

Overview

Given the target scene RGB-D image,AffordDP retrieves a similar object in the affordance memory and transfers its static and dynamic affordance to the target object. Conditioned on 3D affordance, point cloud observation, and robot proprioception, AffordDP utilizes the Diffusion Policy and adaptive affordance guidance for precise control.

Simulation Results





Real world Results


Open Door


Pull Drawer


Pick and Place


Generalizability


Generalize to unseen instances


Generalize to unseen categories


Generalize to unseen scenes


Comparison with Baselines


We benchmark AffordDP against baselines including Diffusion Policy and DP3 in different scenarios. Diffusion Policy and DP3 struggles to perform successfully in out-of-distribution scenarios. In contrast, AffordDP effectively addresses this issue by leveraging affordance transfer. Here are some sample comparative videos:


Unseen instances manipulation in simulation

❌Diffusion Policy

❌DP3

✅AffordDP


Unseen categories manipulation in simulation

❌Diffusion Policy

❌DP3

✅AffordDP


Unseen categories manipulation in real-world

❌Diffusion Policy

❌DP3

✅AffordDP


Ablation study

❌AffordDP without adaptive affordane guidance

✅AffordDP