Dream What I Can: Sparse Visual Planning for
Long-Horizon Robot Manipulation

Chongkai Gao1,2 Wenlong Huang1 Haonan Chen1,3 Lin Shao2 Yilun Du3 Jiajun Wu1 Ruohan Zhang4 Li Fei-Fei1

The world is not made of words

We introduce DreamCan, a sparse visual planner that can generate a sequence of sparse keyframes for robot manipulation task planning. Rather than generating dense frames, DreamCan generates visual subgoals that balance reachability—what the robot can achieve—and task utility—what moves the task forward.

Video

Key Results

Method

DreamCan first employs an unsupervised approach to discover sparse visual subgoal sequences from robot video datasets that balance subgoal reachability and utility, then fine-tunes a pretrained video generation model (WAN 2.2 TI2V-5B) to generate the full sequence of subgoals.

Select a stage to view its details.

Step 1 of 4

Input
Robot video datasets.
Output
A reachability value network that estimates the reachability R∈[0,1] between two states.

DreamCan first learns a Reachability Value Function from action-free videos to measure transition difficulty between two frames.

What does reachability measure?

  • An RL value. In an MDP, VRπ is the expected discounted return for reaching frame sj from frame si: −1 per step until arrival, then 0.
  • A score between 0 and 1. Normalizing this value gives reachability. Earlier arrival means a higher score; τij is the first hitting time.
Rπ(si,sj)=Eπ[γτij] =1+(1−γ)VRπ(si,sj)∈[0,1]

How is it learned?

  • Learn from video transitions. Fit VRθ using an action-free, goal-conditioned variant of Implicit Q-Learning (IQL), an offline RL method.
  • Favor higher returns. An upper-expectile loss emphasizes transitions that reach the conditioning frame more efficiently.
Training objective & sampling

For video transitions D, termination flag di and target head θ¯, the TD target and expectile loss are:

yi=ri+γ(1−di)VRθ¯(si+1,sj) δi=yi−VRθ(si,sj) Lα=ED[|α−1δi<0|δi2]

The upper expectile favors higher-return transitions. We use α=0.75, γ=0.95 and Polyak rate ρ=0.005, with VR(sj,sj)=0. Second frames are sampled equally from future frames with geometric offsets and other trajectories.

Reachability value network

Frame i observation history and frame j pass through a shared frozen RADIO encoder. A temporal Transformer encodes the history, an MLP encodes frame j, and a language encoder provides instruction context. Their features are fused by a value MLP to predict V R of state i and state j, then normalized to reachability R in zero to one.
Explore the learned value

Language Instruction:

Loading learned reachability data…

Experimental Results

Select an option to explore the experiments.

Experiment Suite 1 of 6

Dataset
Three long-horizon tasks from the Language-Table dataset: Make a line, All to region, and Canonical shape.
Train & Eval
We train on 1,424, 1,303, and 1,378 videos for Make a line, All to region, and Canonical shape, respectively, and evaluate on 100 videos per task. Planning success requires reaching the instructed goal, preserving all blocks, and maintaining valid transitions.

Language Instruction: Loading planning examples…

Planning success rate ↑
MethodSuccess rate
Dense planning71%
Uniform planning69%
VLP56%
Ours86%
DreamCan (Ours)

Baselines

Dense planning
Uniform planning
VLP
Video to be added

Interactive Demo

Drag the eight Language-Table blocks into any layout, pick a make-a-line instruction, and the DreamCan planner (Wan 2.2 TI2V-5B at 640×384 with our subgoal LoRA) generates the 16-step visual plan from that start frame. Every plan runs anchored test-time search with a detection-based block guard: each accepted subgoal is checked against the previous one and hallucinated blocks are removed before the next step.

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FAQ

What is DreamCan?

DreamCan is a hierarchical robot manipulation system with a high-level sparse visual planner and an independently trained, goal-conditioned low-level policy. Given the current image observation and a language instruction, the planner predicts a short sequence of visual subgoals. The policy turns these subgoals into robot actions, and the planner is periodically called again using the latest observation for closed-loop replanning.

Why plan with sparse visual subgoals instead of language or dense videos?

Language plans can leave contact locations, geometric relationships, and intermediate object configurations ambiguous. Dense video plans are expensive to generate and can accumulate prediction errors or overconstrain the controller. Uniformly spaced keyframes can include redundant motion, regressions, or transitions that are difficult to execute. DreamCan selects sparse subgoals that balance reachability with useful task progress.

What does the reachability value function measure?

The normalized reachability score estimates how quickly and reliably one visual state can be reached from another. It is a discounted first-hitting-time value, rather than a success probability within a fixed horizon. The model uses action-free, goal-conditioned expectile learning with frozen RADIO visual features.

The learned score is a proxy for dataset-supported reachability, assuming a downstream controller whose capabilities are broadly compatible with the recorded behavior. It is not simply a penalty for elapsed video time: the paper evaluates demonstrations with detours and repeated states to distinguish the two.

How do the planner and low-level policy communicate?

Their interface is the generated subgoal images; the planner and policy do not share gradients or hidden representations. The low-level controller is a 0.1B-parameter goal-conditioned flow-matching Transformer. It uses current visual observations, proprioceptive state, the language instruction, and several future subgoals to produce an action chunk.

The 0.1B parameter count refers only to the low-level policy. The high-level planner is adapted from a 5B-parameter pretrained video model.

How do test-time search and language steering work?

The paper evaluates whole-sequence best-of-N search and anchored search. Anchored search samples candidate continuations, commits a selected prefix as clean latents, and regenerates the remaining subgoals. Candidate plans are evaluated with task-progress scores, and additional generator calls improve planning progress in the evaluated settings.

The planner is conditioned on language instructions. For test-time steering, the paper also uses a vision-language model to write instruction-specific task-progress functions that select plans matching the requested outcome. Examples include different line arrangements in Language-Table and preferred object placements during box packing.

Citation

bibtex
@article{gao2026dreamcan,
  title={Dream What I Can: Sparse Visual Planning for Long-Horizon Robot Manipulation},
  author={Gao, Chongkai and Huang, Wenlong and Chen, Haonan and Shao, Lin and Du, Yilun and Wu, Jiajun and Zhang, Ruohan and Li, Fei-Fei},
  journal={},
  year={2026}
}