XPENG-Backed GroundingPI Is an Open-Source “Eyes” Model for Robots, and It Beats Bigger AI on Perception Tests

GroundingPI, a 4B-parameter open-source perception model backed by XPENG, tops 44 rivals on 34 benchmarks in its team’s tests. Weights are public.

Editorial illustration of a robot arm with glowing bounding boxes around cups and objects on a table.
AI-generated Rovivox illustration.

Robots don’t just need to think. They need to see exactly where things are. A new open-source model backed by Chinese EV and robotics company XPENG targets that problem directly.

GroundingPI is a visual perception model of about 4 billion parameters, developed by researchers affiliated with XPENG, Peking University, the University of Hong Kong and other institutions, XPENG announced on November 4. The paper, model weights and code are public on GitHub and Hugging Face.

Finding “the handle of the cup on the right”
Instead of training on robot actions, GroundingPI focuses on the basics: identifying objects and pinpointing where they are, using points and bounding boxes. XPENG’s example is an instruction like “the handle of the cup on the right,” where a robot must find the right cup and then the exact spot on it.

The model is trained across 11 categories of perception skills, including object detection, dense object localisation, text recognition, document layout, user-interface elements and robot spatial localisation.

The benchmark claims
In the research team’s own evaluation, GroundingPI scored an average of 73.68 across 34 public perception benchmarks, the highest of 44 baseline models, ahead of GPT-6 Astra at 71.54. XPENG notes this covers perception tasks only, not general intelligence or reasoning. These are the team’s results and have not yet been independently replicated.

In simulation, robot-learning systems using GroundingPI as their “eyes” reportedly reached higher success rates with 50% of the demonstration data than comparison models given 75%, and handled unfamiliar environments better in RoboTwin 2.0 tests.

What it isn’t
XPENG is careful to say the work is exploratory. The robot results come from simulation and offline tests, and the release is not an announcement that GroundingPI will go into XPENG’s products.

Why it matters
Big general-purpose AI models are good at language and planning, but robots fail on the small stuff: grabbing the wrong object or missing by a few centimetres. A compact, open perception model that anyone can download is a practical building block for the industry. The next test is whether it holds up on real robots outside the lab.