# Baffled Circular Piston Radiation Impedance & Directivity Calculator

> Baffled Circular Piston Radiation Impedance & Directivity Calculator is a paid API for AI agents from detect.halowerk.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-11-04).

Computes ideal baffled circular piston radiation loading, radiated power, and signed far-field angular amplitude using Bessel and Struve functions.

## Facts

- Endpoint: POST https://detect.halowerk.com/v1/F-TD2000-GEO-INDUSTRY-B009/baffled-circular-piston-bessel-struve-radiation-impedance-directivity?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-04
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/baffled-circular-piston-radiation-impedance-directivity-calculator-2c32cd60
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oLxkgL3PUk9srJ_ybCbdo

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 baffled-circular-piston-radiation-impedance-directivity-calculator-2c32cd60 -d '<json body>'
```

Example prompt: Compute the baffled circular piston radiation impedance, radiated power, and signed far-field directivity for a piston with radius 0.05 m, operating at 5000 Hz in air (sound speed 343 m/s, density 1.21 kg/m³, velocity amplitude 0.01 m/s), evaluated at angles 0, 0.3, 0.6, 0.9, and 1.2 radians.

## When to prefer this

Use this endpoint when you need analytically rigorous, Bessel/Struve-function-based computation of baffled circular piston acoustics — including radiation impedance (loading), radiated power, and signed far-field directivity — in a single call. Prefer this over numerical FEM solvers when the geometry is exactly a baffled circular piston and analytical precision at fast turnaround is required. Ideal for transducer design, beam pattern characterization, and acoustic impedance matching workflows.

## Known failure modes

- Radius out of range (must be 0.000001–100 m) returns validation error
- Frequency outside 0.01–1,000,000 Hz returns schema error
- Angles array must contain 1–32 values each in [0, π/2] radians
- Sound speed below 1 or above 10,000 m/s rejected
- Zero velocity amplitude may produce degenerate zero-power output
- Missing required fields (radius, frequency_hz, sound_speed, density, velocity_amplitude, angles_radians) causes 422

## How this service works

Compute ideal piston radiation loading,power and signed far-field angular amplitude.

## Output

Returns the radiation impedance (resistance and reactance components representing acoustic loading), total radiated acoustic power, and the signed far-field angular amplitude values at each requested observation angle — enabling full characterization of a baffled piston's acoustic performance.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "artifact": {
   "type": "object",
   "required": [
    "acousticPiston"
   ],
   "properties": {
    "acousticPiston": {
     "type": "object",
     "required": [
      "data",
      "claim"
     ],
     "properties": {
      "data": {
       "type": "object",
       "required": [
        "radius",
        "frequency_hz",
        "sound_speed",
        "density",
        "velocity_amplitude",
        "angles_radians"
       ],
       "properties": {
        "radius": {
         "type": "number",
         "maximum": 100,
         "minimum": 0.000001
        },
        "density": {
         "type": "number",
         "maximum": 10000,
         "minimum": 0.001
        },
        "sound_speed": {
         "type": "number",
         "maximum": 10000,
         "minimum": 1
        },
        "frequency_hz": {
         "type": "number",
         "maximum": 1000000,
         "minimum": 0.01
        },
        "angles_radians": {
         "type": "array",
         "items": {
          "type": "number",
          "maximum": 1.5707963267948966,
          "minimum": 0
         },
         "maxItems": 32,
         "minItems": 1
        },
        "velocity_amplitude": {
         "type": "number",
         "maximum": 100,
         "minimum": 0
        }
       },
       "additionalProperties": false
      },
      "claim": {}
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/baffled-circular-piston-radiation-impedance-directivity-calculator-2c32cd60/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from detect.halowerk.com](https://www.zero.xyz/host/detect.halowerk.com/llms.txt)