Canvas 3 — Training & Post-Training Foundation and VLA Models

How to use this canvas

This canvas covers how open foundation models are turned into policies and perception models for heavy industrial machines (construction, mining and earth-moving autonomy): supervised fine-tuning, VLA post-training, reinforcement learning (RL), and the multi-GPU training workflows behind them. It is canvas 3 of 9 and follows a research-area exploration framework, with the Emerging (11–12) and Applied (13) modules added.

BoundaryOwned hereOwned elsewhere
DataData-mix recipes and how datasets are consumed during trainingBuilding and versioning datasets (canvas 1)
SimulationRL algorithms and training loops that use simulated environmentsBuilding the environments and physics (canvas 2)
EvaluationTraining-time validation and checkpoint selectionRelease-gating evaluation and safety evidence (canvas 4)
Model lifecycleProducing checkpoints with full training metadataRegistry, promotion and governance (canvas 5)
ComputeParallelism strategy, memory and throughput per jobCluster scheduling, queues and quotas (canvas 6)
DeploymentTraining for the target latency and hardware (e.g. action chunking for an embedded GPU module)Quantization, TensorRT and serving (canvas 7)

1. Core definition and scope

Definition. A vision-language-action (VLA) model maps camera images, a language instruction and the machine's state to actions. Most current VLAs pair a pretrained vision-language model (VLM) with an action head. NVIDIA's GR00T N1.6, for example, is a 3-billion-parameter open VLA that combines a Cosmos-family VLM with a 32-layer diffusion transformer action head (NVIDIA).

Post-training adapts such a pretrained model to a specific machine, task and environment. It now has two parts: supervised fine-tuning (SFT) on demonstrations, and RL from rewards, interventions or autonomous practice. The field's working view is that pretrained VLAs still need fine-tuning for real deployment, and imitation alone generalizes poorly outside its data (RL-VLA survey).

Training workflow covers everything around those steps: data loading, parallelism across many GPUs, checkpoints, experiment tracking and reproducibility.

Training stack from base model to evaluation
training stack · 7 stages owned here

The top row adapts an open model to a heavy machine; the bottom row improves it with real experience and shrinks it for the machine before evaluation and registration.

Key sub-domains

Sub-domainCore questionTypical artifacts
Base model selectionWhich pretrained VLA, VLM or perception backbone is the starting point?Model cards, licence review, baseline scores
Embodiment adaptationHow are a machine's joints, hydraulics and cameras mapped into the model?Action space definition, state normalization, camera config
Supervised fine-tuningHow much demonstration data, and which parameters to train?SFT recipes, LoRA adapters, data-mix ratios
RL post-trainingHow to improve beyond demonstrations?Reward models, RL configs, intervention logs
Perception and world modelsHow to fine-tune detectors, segmenters and world models for jobsites and mines?Fine-tuned Cosmos models, perception checkpoints
Distributed trainingHow to train efficiently on many GPUs?Parallelism configs (FSDP, tensor, pipeline), throughput reports
ReproducibilityCan any checkpoint be rebuilt exactly?Run manifests: code, data version, config, seed, environment

Debate. One camp builds one large cross-machine foundation model for every machine type. The other fine-tunes smaller specialist models per machine family. The answer depends on whether data from different machines transfers positively, which is still open (canvas 1).

2. Historical context and evolution

In four years robot learning moved from task-specific policies to open foundation models that are fine-tuned per robot, and then to models that keep improving from deployment through RL.

YearMilestoneWhy it matters here
2026Gemini Robotics 2 and On-Device 2 (July): on-device VLA adapts to new embodiments with a few hours of dataFast embodiment adaptation becomes a product feature
2026Physical Intelligence RL tokens (March): precise skills from minutes to hours of real-world RLReal-world RL becomes practical for fine, precise tasks
2026GR00T N1.6 public launch at CES; SimpleVLA-RL at ICLR (proceedings)Open VLA plus open RL tooling
2025π*0.6 with RECAP (November): RL from autonomous rollouts and human corrections more than doubles throughput on the hardest tasksRL post-training from real deployment
2025GR00T N1.6 (December), N1/N1.5 earlier; Gemini Robotics 1.5 (September); OpenVLA-OFT (February)Open models and a proven fine-tuning recipe
2024OpenVLA (7B, open); Octo; π₀ flow-matching VLAFirst open VLAs that labs could fine-tune
2023RT-2 (VLM backbone emits actions); Open X-Embodiment and RT-X; Diffusion Policy; ACTVLMs become robot controllers; cross-robot data helps
2022RT-1 (Google): transformer policy on 130k demonstrationsLarge-scale imitation works on real robots
2017–2021Deep RL in simulation (PPO, SAC); sim-to-real locomotionRL works where simulation is good

Paradigm shifts

  1. From training per task to fine-tuning a foundation model. Pretrained VLAs carry general visual and language knowledge.

  2. From token actions to continuous action heads. Autoregressive action tokens ran at 3–5 Hz; parallel decoding with action chunks reaches 25 Hz and above (OpenVLA-OFT).

  3. From imitation only to imitation plus RL. As with LLMs, RL after SFT is becoming standard (SimpleVLA-RL).

  4. From one model to planner plus actor. Reasoning models plan and call VLAs to act, as in Gemini Robotics-ER with Gemini Robotics.

3. Current state of research

The standard recipe in 2026 is pretrained VLM + action expert, fine-tuned on a small machine-specific dataset, then improved with RL. What remains unsettled is how much each stage contributes and how to do RL safely on real machines.

Dominant frameworks

Key research questions

QuestionState of evidence
How little demonstration data does a new machine need?Hours, for embodiments close to pretraining data (Gemini Robotics On-Device 2); unknown for hydraulic heavy machines
Does RL beat more demonstrations?SimpleVLA-RL beats SFT in simulation and real tasks under data scarcity (ICLR 2026)
Can RL run safely on real machines?Shown on arms with human supervision; no public evidence found for 20–200-tonne machines
Which parameters to tune?Full fine-tuning, LoRA, frozen backbone with trained action expert all in use; trade-offs depend on data size
How to avoid forgetting general skills?Co-training with pretraining data and regularization; still an active topic
Do models transfer across very different bodies?Positive within arms and humanoids; heavy machines are far from the pretraining mix

Challenges for heavy equipment

Debates

4. Key stakeholders and research centers

A handful of labs set the VLA agenda; heavy-equipment learning is a small field led by university groups, autonomy start-ups and machine makers in Asia, Europe and North America.

ClusterWhoContribution to this canvas
Open VLA platformsNVIDIA GEAR lab (GR00T N1–N1.6; Isaac-GR00T repo); Physical Intelligence (openpi, π₀ to π*0.6); Stanford (OpenVLA, OpenVLA-OFT: Kim, Finn, Liang); Hugging Face LeRobot (SmolVLA)Open checkpoints and fine-tuning code a platform can adopt
Closed frontier VLAsGoogle DeepMind (Gemini Robotics 2, ER 2, On-Device 2); Tesla, Figure (in-house)Benchmarks for what is possible; partner-access models
RL post-trainingPhysical Intelligence (RECAP, RL tokens); Tsinghua/Shanghai AI Lab (SimpleVLA-RL); RLinf team (RLinf-VLA); UC Berkeley (Levine)Methods for improving VLAs beyond demonstrations
Training infrastructureNVIDIA NeMo (Megatron-Core, NeMo-RL, AutoModel); PyTorch (FSDP2, TorchTitan); Ray; VLA FoundryDistributed training and RL frameworks
Heavy-equipment learningETH Zurich RSL (Hutter; HEAP walking excavator); Baidu Research (ExACT, ExT: arXiv 2509.14992); Tampere University (Mattila: IL-ACT, 30-tonne excavator)The few groups applying imitation, RL and foundation models to excavators

Inside heavy-equipment OEMs and autonomy developers (public evidence).

No public source reviewed for this canvas documents a production heavy-machine VLA post-trained at scale; most published excavator learning work comes from university groups (see section 9).

Debate. Open models (GR00T, openpi, OpenVLA) give control and on-prem training but lag the closed frontier; closed partner models (Gemini Robotics) may perform better but limit how a machine maker can fine-tune, deploy and certify them.

5. Methodological landscape

Methods group by training stage. Each has a default that works today and a frontier.

StageDefault methodResearch frontier
Choose a baseOpen VLA (GR00T N1.6, π₀/π₀.₅, OpenVLA) or VLM backbone + new action headDomain pretraining on heavy-machine video and telemetry before task fine-tuning
Define the embodimentMap joints/valves to an action vector; normalize state; state-relative action chunksLearned embodiment adapters that transfer across machine families
Supervised fine-tuningFull fine-tuning or LoRA on demonstrations; co-train with pretraining data (GR00T N1.6)Data-efficient recipes; influence-based demo selection (canvas 1)
Action generationAction chunking with diffusion or flow-matching heads; parallel decodingReal-time chunking for smooth, asynchronous execution on slow hardware
RL in simulationPPO or GRPO-style RL with outcome rewards in Isaac Lab (SimpleVLA-RL)Massively parallel RL for large VLAs (RLinf-VLA)
RL from real experienceOffline RL from logs; advantage-conditioned learning from rollouts and corrections (RECAP)Online RL with safety constraints and human supervision; RL tokens for precision
DistillationLarge teacher to small on-machine studentDistillation that keeps safety-relevant behavior
Perception and world modelsFine-tune detectors, segmenters and Cosmos models on jobsite dataShared backbone between perception and VLA

Distributed training workflow

Data collection for training

Analysis techniques

6. Interdisciplinary connections

Training consumes from canvases 1 and 2 and produces for canvases 4, 5 and 7. Each interface needs a named contract.

Connects toWhat crosses the boundaryContract to define
Canvas 1: data flywheelVersioned datasets and data-mix recipesEvery run pins dataset IDs and manifest hashes
Canvas 2: simulationRL environments and synthetic demonstrationsEnvironment API and versioned environment releases
Canvas 4: evaluationCandidate checkpoints for release testingCheckpoint handoff format; training-time metrics vs release metrics
Canvas 5: MLOps and governanceCheckpoints with full run metadataRun manifest schema; registry entry on success
Canvas 6: GPU infrastructureTraining and RL jobs, multi-nodeJob classes (SFT, RL rollout, RL learner); quotas; preemption rules
Canvas 7: inferenceModels trained for on-machine latency limitsTarget hardware, control rate and chunk size agreed before training
Canvas 8: observability and costGPU hours, utilization, cost per runCost attribution per experiment and team

Outside fields

7. Future directions

The frontier is moving from "fine-tune once" to models that keep learning in deployment. For heavy equipment, the first job is closing the embodiment gap: public VLAs were trained mostly on arms and humanoids, not hydraulic excavators.

Emerging trends

  1. Continual learning from deployment. RECAP-style loops where every shift of autonomous work produces training signal.

  2. Fast embodiment adaptation. Gemini Robotics On-Device 2 adapts to new robot bodies with a few hours of data (DeepMind).

  3. Precision RL with little data. RL tokens learn delicate skills from minutes to hours of practice (Physical Intelligence).

  4. Unified LLM-VLM-VLA training stacks. Frameworks such as VLA Foundry train all three in one codebase (Emergent Mind).

  5. Reasoning plus acting. A reasoning model plans and checks; the VLA acts. Fits jobsite tasks with many steps.

  6. Domain foundation models for construction. Pretraining on diverse excavation demonstrations, then fine-tuning per task, as in ExT (arXiv 2509.14992).

Research gaps in heavy-industry physical AI

GapWhy it is openOpportunity
VLAs for hydraulic heavy machinesPretraining mixes have arms and humanoids, not booms and bucketsDomain pretraining on shared excavation demonstrations and telemetry
Safe RL on real machinesExploration on 20–200-tonne machines is dangerousRL in simulation plus offline RL from logs; constrained online RL on closed test sites
Learned policy above certified controlFew published architectures combine VLAs with functional-safety layersDefine a reference pattern: learned planner, certified low-level control
Rewards for earth-movingProductivity, grade quality and machine wear are hard to combineReward models trained on operator ratings and telemetry
Cross-machine transferUnknown whether excavator skills help dozers or loadersControlled multi-machine training studies
Long-horizon jobsite tasksBenchmarks cover minutes, not shiftsHierarchical planning with measurable sub-goals

Potential breakthroughs (speculative, not forecasts)

8. Resources and infrastructure

Models and frameworks

LayerOpen sourceCommercial / partner access
Open VLAsGR00T N1.6 (3B), π₀ / π₀.₅ / π₀.₆ via openpi, OpenVLA and OpenVLA-OFT, Octo, SmolVLAGemini Robotics 2 and On-Device 2 (early-access partners)
VLM and world-model backbonesCosmos Reason, Qwen-VL, Eagle, PaliGemmaGemini Robotics-ER 2 (API)
Training frameworksPyTorch FSDP2, TorchTitan, NeMo Megatron-Core and AutoModel, Hugging Face Transformers and LeRobotNVIDIA AI Enterprise
RL frameworksNeMo-RL, SimpleVLA-RL, RLinf, Isaac Lab RL games / rsl_rl, veRL—
OrchestrationRay, Kubeflow Training Operator, SlurmNVIDIA OSMO, Run:ai
Experiment trackingMLflow, Weights & Biases (hosted), AimWeights & Biases, Neptune
Training computeDGX systems; GPU cloudsHyperscale and specialist GPU clouds (e.g. Azure, Nebius, CoreWeave)

Benchmarks

Journals and conferences

Funding sources

9. Literature analysis

Read OpenVLA-OFT for fine-tuning practice, π*0.6 for RL from deployment, and ExT and IL-ACT for excavators.

Recent influential works (2025–2026)

YearWorkOne-line takeaway
2026Heydari Shahna et al., IL-ACTImitation policy plus adaptive Cartesian tracking on a 30-tonne excavator model
2026Li et al., SimpleVLA-RL (ICLR)Outcome-reward RL beats SFT under data scarcity
2026RLinf-VLA (RSS)Unified, efficient system for RL on VLAs
2026VLA FoundryOne codebase for LLM, VLM and VLA training; backbone quality matters most
2026Physical Intelligence, RL tokensPrecise skills from short real-world RL
2025Physical Intelligence, π*0.6 / RECAPRL from rollouts and corrections doubles throughput on hard tasks
2025NVIDIA, GR00T N1.6Open 3B VLA; small post-training sets with co-training
2025Kim, Finn, Liang, OpenVLA-OFT (RSS)Fine-tuning recipe: 76.5% to 97.1% on LIBERO; 26x faster action generation
2025ExTPretraining on diverse excavation demos for task-level generalization
2024Chen et al., ExACTEnd-to-end imitation learning from LiDAR, camera and joints to excavator valves

Seminal papers

YearWorkContribution
2024Kim et al., OpenVLAFirst widely used open 7B VLA
2024Black et al., π₀Flow-matching action expert on a VLM
2023Brohan et al., RT-2VLM fine-tuned to output robot actions
2023Chi et al., Diffusion Policy; Zhao et al., ACTAction chunking and diffusion for visuomotor control
2022Brohan et al., RT-1Transformer policy at scale on real robots
2021Hu et al., LoRAParameter-efficient fine-tuning
2017Schulman et al., PPODefault RL algorithm in simulation

Literature reviews to keep open: RL of VLA models survey (TechRxiv 2025); VLA post-training and human motor learning; the 2026 VLA data-infrastructure survey (canvas 1).

Gap in the literature: none of the sources reviewed here reports a VLA post-trained and evaluated on a full-size excavator or dozer at production scale.

10. Practical applications

Models in heavy-industry physical AI fall into three kinds: perception for safety and autonomy, policies for machine control, and language-and-vision models for operator assistance. All three need the same training platform.

ApplicationModel typeTraining approach
Person and obstacle detection around machinesPerception (detector, segmenter)SFT on fleet and synthetic data; frequent retraining from the data flywheel
Construction autonomy: excavator digging, loading, trenchingVLA or imitation policyDemonstrations from skilled operators, then RL in simulation and offline RL from logs
Dozer grading, compactor passesPolicy with plannerImitation plus RL on grade-accuracy rewards
Mining haulage and drilling autonomyPerception and planningSupervised training on fleet data; scenario-driven retraining
In-cab and operator assistanceSpeech, VLM and compact LLMFine-tuning on manuals, fault codes and service data; runs on embedded GPU modules
Jobsite digital twins and understandingWorld models (Cosmos post-training)Fine-tune on jobsite video for prediction and augmentation
Predictive maintenanceTime-series modelsSupervised training on telemetry and repair records

Industry connections

Future applications (speculative): one foundation policy family across excavators, loaders and dozers; operator-assist features (auto-dig, auto-grade) trained with the same stack as full autonomy, so data and models are shared.

11–12. Technology integration, ethics and regulation

Technology integration

Ethical considerations

Regulatory requirements

RuleWhat it means for training
EU Machinery Regulation 2023/1230 (from 20 January 2027)Machines whose safety functions use self-learning behavior need third-party assessment; models that keep learning after sale face the strictest route
EU AI Act as amended by Regulation (EU) 2026/1744 (in force 27 July 2026)Machinery is no longer in the Act's direct high-risk scope; equivalent rules are expected through Machinery Regulation delegated acts. Where high-risk duties apply (from 2 Dec 2027 / 2 Aug 2028): documented training methods, data governance and logging
ISO 17757:2019; ISO 13849Learned components must sit inside a safety architecture that meets functional-safety requirements
Model licencesSome open checkpoints (e.g. GR00T task models) are non-commercial; legal review before production use

Implication: in the near term, train offline and release frozen, versioned models through evaluation gates (canvas 4). Learning on customer machines after sale is a regulatory step change and needs its own decision.

13. Implementation framework

Build in four phases. Make training reproducible before making it clever: RL and continual learning amplify any untracked change in data or code.

Reproducible fine-tuning first, then RL, then a domain foundation modelPhase 1Reproducible SFTRun manifestsBaseline policiesOne machine, one taskPhase 2RL in simulationSimulated environmentsReward designSim-to-real checkPhase 3Real-world RLOffline RL from logsTest-site RLSafety envelopePhase 4Domain foundationDomain pretrainingMulti-machine dataDistill for edge computeGate: runs reproducibleGate: RL beats SFTGate: site gain shown
training rollout · 4 phases, 3 gates

Phases are sequenced, not dated. Phase 1 is highlighted because RL and foundation-scale training only pay off once every run can be reproduced.

Required resources

Risk assessment (likelihood and impact are the author's qualitative estimates)

RiskLikelihoodImpactMitigation
Open VLAs transfer poorly to hydraulic machinesHighHighBudget for domain-specific pretraining; keep a classical or imitation baseline
RL causes unsafe behavior on test machinesMediumHighRL in simulation first; offline RL from logs; hard safety envelopes on real machines
Runs can't be reproducedMediumHighRun manifests mandatory; registry rejects checkpoints without them (canvas 5)
GPU shortage slows iterationMediumMediumQuotas and priority classes (canvas 6); cloud burst
Licence limits on base modelsMediumHighLegal review per base model; prefer permissive licences for production
Catastrophic forgetting during post-trainingMediumMediumCo-training with pretraining data; regression suites (canvas 4)

Success metrics

MetricWhat it shows
Task success rate on test sites, per machine and taskPolicy quality
Interventions per operating hourReadiness for autonomy
Demonstration hours needed for a new taskData efficiency
Gain from RL over SFT (%)Value of RL post-training
Time from new data to evaluated checkpoint (days)Iteration speed
GPU utilization of training jobs (%)Infrastructure efficiency
Runs with complete manifests (%)Reproducibility

Set targets after phase 1 baselines.

Open questions and follow-up prompts

Open questions for practitioners

Follow-up prompts (from the research-area framework)

  1. Elaborate on an action-space design for hydraulic excavators that works with GR00T N1.6 or π₀-style action heads.

  2. Provide detailed methods for RL post-training of a digging policy: simulation, offline RL and supervised real-world RL.

  3. Analyze the challenges of combining a VLA planner with a certified low-level controller.

  4. Suggest an experiment testing whether excavator data improves a wheel-loader policy.

Sources