# HALOWERK OpenCV Robot Hand-Eye Calibration

> HALOWERK OpenCV Robot Hand-Eye Calibration is a paid API for AI agents from medien.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-30).

Computes the rigid camera-to-gripper transform from synchronized gripper-to-base and target-to-camera pose pairs using OpenCV hand-eye calibration

## Facts

- Endpoint: POST https://medien.halowerk.com/v1/oss-opencv-robot-hand-eye-calibrate?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-opencv-robot-hand-eye-calibration-f7c280af
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hwYBwbI4Vexdr3g6qFYYa

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability halowerk-opencv-robot-hand-eye-calibration-f7c280af -d '<json body>'
```

Example prompt: I have 10 synchronized pose pairs from my robot arm — the gripper-to-base 4x4 matrices and the matching target-to-camera 4x4 matrices — can you run hand-eye calibration to figure out the rigid transform between the camera and the gripper?

## When to prefer this

Choose this endpoint when you need a fast, pay-per-call hand-eye calibration computation backed by OpenCV without managing local dependencies. It is ideal for robotics pipelines that already collect synchronized pose data and need to periodically recompute the camera-to-gripper transform, especially in cloud-deployed or agent-driven automation workflows where installing OpenCV locally is impractical.

## Known failure modes

- Fewer than 3 pose pairs provided — minimum 3 required
- Mismatched array lengths between gripper_to_base and target_to_camera — pairs must correspond exactly
- Off-by-one synchronization error in input poses produces a plausible but entirely incorrect transform with no detectable error signal
- Non-rigid or degenerate motion between poses causes numerically unstable calibration
- Malformed 4x4 matrix (wrong dimensions) returns a validation error
- Insufficient motion diversity in the pose sequence leads to poorly conditioned solution

## How this service works

Solves the hand-eye problem: given a series of gripper-to-base poses read from the robot and the matching target-to-camera poses seen by the camera, it recovers the rigid transform between camera and gripper that stays constant as the arm moves. This is what lets a robot act on what its camera sees. The poses must be genuinely synchronized — a pairing that is off by one sample produces a confident and entirely wrong transform, and nothing in the data reveals it.

## Output

Returns the recovered 4x4 rigid transformation matrix representing the constant camera-to-gripper (or gripper-to-camera) transform, enabling the robot to map camera observations into the robot's coordinate frame.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "gripper_to_base": {
   "type": "array",
   "items": {
    "type": "array",
    "items": {
     "type": "array",
     "items": {
      "type": "number",
      "maximum": 1000000000,
      "minimum": -1000000000
     },
     "maxItems": 4,
     "minItems": 4
    },
    "maxItems": 4,
    "minItems": 4
   },
   "maxItems": 32,
   "minItems": 3
  },
  "target_to_camera": {
   "type": "array",
   "items": {
    "type": "array",
    "items": {
     "type": "array",
     "items": {
      "type": "number",
      "maximum": 1000000000,
      "minimum": -1000000000
     },
     "maxItems": 4,
     "minItems": 4
    },
    "maxItems": 4,
    "minItems": 4
   },
   "maxItems": 32,
   "minItems": 3
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-opencv-robot-hand-eye-calibration-f7c280af/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from medien.halowerk.com](https://www.zero.xyz/host/medien.halowerk.com/llms.txt)