UBR Stack · team 15 · NVIDIA Open Models Codefest 2026
Codefest Blocker Board
Where we need something from you, ordered by what it costs us.
Seven questions and one offer. Only two need a yes or a no: an
ambiguity in the Transfer documentation, and a licence reading we have already acted on and now
need confirmed or reversed. The offer is not a question at all — a 4B reasoner running in ~4,830 MB
on an 8 GB edge board, with the number that went wrong reported next to the numbers that went
right.
2 · need a yes or no
2 · costs throughput
3 · costs accuracy or planning
1 · offered, not asked
Stops work
The two we cannot resolve ourselves
1
Cosmos Transfer 2.5 — which control stack keeps Replicator's boxes valid?
Needs a yes or no
The constraint
We run Transfer 2.5 on Isaac orbit clips, and the renderer's COCO boxes must still describe
the output. Our plan said segmentation control alone; the cookbook says seg should always be
used with a mask and as part of multi-control, and the photoreal recipe is
edge 1.0 + seg 0.9 + depth 0.9 at guidance 7.
The ask
Is that the right starting point for Replicator output where geometry must not move
at all — or does edge at 1.0 suppress exactly the appearance change we are paying for? If
edge must come down, what range still holds geometry? And since weights above 1.0 are
renormalised to sum to 1.0, are the documented values pre- or post-normalisation? We
would rather not sweep around a misread scale.
What we are doing anyway
A 13-clip × 3-strength sweep, scoring label survival two ways — an impartial detector, and
Cosmos3-Super judging "person lying, and where" against the renderer's box. A correct starting
configuration saves a day of B300 time.
2
Isaac-rendered images: we have taken a licence position and published it. Confirm it, or tell us to pull it.
Needs a yes or no
What is public, exactly
ubr-physical-ai/isaac-sdg-rescue-target is public and
un-gated, with three revisions live: main,
v2 (23,960 images, 14 classes, night and fog, out to 30 m) and
v3 (37 webdataset shards, 18.68 GB, plus 109 masked
93-frame orbit clips). Hugging Face visibility is per-repository, not per-branch, so
revision="v3" is downloadable by anyone today. 26 downloads so far.
An earlier draft of this page said we were holding it. That was wrong, and this is the
correction.
The position we took
The v2 and v3 cards split the licence rather than claiming CC BY 4.0 outright:
annotations, metadata, configs and card CC BY 4.0 (UB Robotics); images
rendered from NVIDIA-distributed assets, with the note that the Isaac Sim Additional
Software and Materials License forbids redistributing assets and does not address
rendered output. No source assets are included — renders only. The repository's own
licence tag, however, still reads a flat cc-by-4.0, so the Hugging Face
page advertises more than the cards do. That mismatch is ours to fix and we are fixing it.
The ask
Does that reading hold? A yes lets us align the repository tag to the cards and keep
going. A no is equally useful and we act on it the same day: we can make the repository
private, drop the affected revisions, or re-render with our own assets — tell us which
and it is done. We would rather hear it from you now than from someone else in week 4.
Why we did not wait
Because the honest version of this question is not "may we?" but "we have, on this
reading — is it right?" The public developer-forum thread asking exactly this was closed
with "contact Enterprise Sales", and a public dataset plus protocol is one of our Codefest
deliverables. Publishing and then asking is a position we can defend; asking while quietly
already published is not.
Offered, not asked
One result we would like to hand over
Getting a 4B VLM onto an 8 GB Orin Nano was our job, not yours, and it is done —
it runs, fast, and fits the 8 GB board with room to spare. It also gets the answers wrong in a specific and
interesting way. Both halves are below, because the half that worked is not the useful half.
◆
Cosmos3-Edge INT4 on Orin Nano 8 GB — it runs. Here are the numbers, and the one failure we cannot diagnose.
Offer
What we built
INT4 AWQ quantisation and ONNX export on a B300, engine and
visual_build on a bench Orin Nano at JetPack 7.2 / CUDA 13.2,
TensorRT Edge-LLM v0.10.1 (e8b2952).
Calibrated on 198 frames drawn from a frozen 256-frame slice of our own rover
footage, disjoint from every set we later score on. 169 INT4 nodes verified in the
built engine; build time 2 m 21 s.
What it costs on the board — the half that worked
llm.engine 838.9 MiB + visual.engine
942 MiB + embeddings 512 MiB = 2.24 GiB of artefacts. Peak resident ~4,830 MB
for the full VLM (3,377 MB the LLM engine alone), against 7,485 MB usable. Decode
52.8 tok/s (18.92 ms/token), prefill 2,306 tok/s, visual encoder 259.8 ms at
896×448 — so camera frame to decision is 633 ms at 8 output tokens, 1,087 ms at 32.
Earlier arms on the same board, for scale:
NF4 2.67 GiB @ 8.67 tok/s · bf16 4.58 GiB @ 10.6 tok/s.
One correction worth stating: it does not fit the 4 GB variant — even the 3,377 MB
LLM engine alone exceeds the roughly 1,900–2,200 MB free after the OS.
What it gets wrong — the half that matters
Grounded F1 0.0 on a 24-item set; 0 of 12 targets found; 0 of 24 outputs obey
the output schema. The failure is not truncation or parsing: results are
identical at 192 and 512 token caps, 23 of 24 ended on end-of-sequence, and 24 of 24 are
well-formed JSON with no fences. They ignore the contract — 10 omit
task_relevance on entities, 14 omit
certainty on attributes, several emit out-of-enum values, 3 hoist
a field to the top level, 2 drop schema_version. The earlier NF4
arm on the same board scored F1 0.40 with 3 of 24 schema-valid — paired, that is a 3–0
discordance, exact p = 0.25, so we are not claiming AWQ is worse than NF4.
The two things we cannot find out ourselves
Is a 4-bit instruction-following regression known for this model? We cannot run the
control that would settle it: full precision needs ~9 GiB and will not fit the 7.3 GB
board, so we cannot ask whether bf16 honours the same contract on the same hardware. If you
already know that a W4A16 AWQ build stops honouring a JSON schema the full-precision model
honours, that closes the question today. Does Edge-LLM expose constrained decoding at v0.10.1 — a logit processor, a grammar,
anything that forces the output shape at decode time? If it does, the fix is hours rather
than a training run, and it is the serving behaviour a rover needs regardless.
What we can and cannot hand over
The prompt template (frozen text) and the scorer (stdlib only) are yours if
you want them, and they are enough to reproduce the failure on your own images. The 24
evaluation items are frames of identifiable people in a workplace, so they do not leave our
bench and we cannot send them — metrics and structural diagnostics only. If the artefact is
useful, tell us who should review it and we will write it up to whatever standard you need;
we read the model card as OpenMDW 1.1 and take publishing a derived engine to be permitted.
Either way
This is reportable as it stands. "A 4B reasoner fits an 8 GB edge board at ~4,830 MB and
633 ms to a decision, and then fails on output contracts" is a more useful finding for anyone
deploying these than a number that flattered us.
Costs throughput
We can work around these, slower
3
Is there an RT-core node in the cluster for Isaac Sim?
Open
Why we ask
Isaac Sim 6.0's requirements state that GPUs without RT cores (A100, H100) are not
supported, so the B300 cannot render and all Isaac work runs on one RTX 4060 Ti 16 GB
workstation of ours — below Isaac 6.0's own recommended tier. That box is now
double-booked: the SDG render backlog and the closed-loop sim missions, where the
renderer and the reasoner share the one card.
What it already costs us
Because renderer and brain share a GPU, that layer can report mission outcomes but
cannot produce deployment latency figures — those come only from the Orin. We had to
narrow what the layer is allowed to claim, and retire a sim-to-real subtraction we had
designed the evaluation around.
The ask
Is an L40S or RTX PRO 6000 node available, or is local-render plus cluster-train the
expected split? Without a node we sequence the two and document it — we would rather not
discover that in week 3.
4
One B300, three GPU-bound jobs queued
Open
Serialising on the single card
The Transfer 2.5 strength sweep; the round-2 4-bit accuracy arms (same 986 pairs and
harness as round 1, so the quantisation delta is measured on matched hardware); and one
Cosmos3-Super pass as teacher and QC judge over the Transfer output.
The ask
Is a second card available for the Transfer week? Smaller, same topic: our detector sweeps
turned out CPU-bound rather than GPU-bound (16 CPUs, load 16.7), so we now submit with
--cpus-per-task=32. Is there a per-task CPU ceiling, or a queue
convention we should be using better?
And one we should have raised sooner
dgx02 has been sitting in IDLE+DRAIN,
and our team storage lives on it. We do not know whether that is planned maintenance
or a fault, and we have been working around it instead of asking — which was the wrong
call. Is it coming back, and should we be staging our data somewhere else?
Costs accuracy or planning time
Would help, and shapes what we build next
5
A small-scale or LoRA SFT configuration for Cosmos3-Edge
Open
What we are aiming at
The SFT target moved on 11 Sep. L0 shows 4-bit costs nothing once calibrated; the perception false-alarm rate is under re-measurement on the 474-frame slice. Any SFT budget now goes to the operator-language side: the August tool-calling gate
(0 of 21) re-run under the conversational prompt that carried commands to 13/15, and an
UNKNOWN reply so the model can decline rather than force a command. A text-only Gemma
E2B (14/14 including Portuguese) is the measured fallback if training is not ready in time.
Why the published path does not fit
The post-training write-up we found is 76k DROID trajectories on 64 nodes of 4× GB200,
~17.4K GB200-hours — and it goes through cosmos-framework, which we
had to drop from our container because it pins transformers < 5 and breaks vLLM and the
guardrail.
The ask
Is there a LoRA or small-data SFT configuration for the 2.4B/4B reasoner that is known not
to damage what it already does well (65.2 % on left/right)? And does post-training invalidate
the INT4 path — requantise, re-export and rebuild, or can an existing engine be reused?
6
Rover-height person data — anything at ~0.5 m, ideally prone?
Open
Checked and ruled out for that viewpoint
Spatial-Intelligence-Warehouse, SmartSpaces 2026 (including both real warehouse captures),
NuRec, SDG-SynHuman, Embodied-Robot-Scenes — all ceiling, drone or humanoid viewpoint. We use
them as negatives and for spatial QA, and render the positives ourselves.
The ask
Is there a PhysicalAI subset at ground-robot height with low or prone poses that we have
missed?
Why we care
Our real-side instrument is a frozen 474-frame slice of past rover missions (max 2
frames per segment, minimum dHash Hamming 12 across the selection). It is dense in standing
and walking people and almost empty of lying ones — hence a mannequin capture to supply the
positives and the measured distances.
7
Showcase format for GTC Berlin
Open
The ask
How long is the top-5 slot, and is it a live demo, a recorded demo or slides?
What it changes
Week 4. If a live run is viable we bring the rover and pull the network cable on stage; if
it is recorded, we shoot in week 3 and spend week 4 on the numbers.