# Helical gear mesh

> Connection kind `helical-mesh` (category `mech`, DSL name `helicalMesh`, API v1)

Couples two helical gears of the same normal module on parallel axes. A mating pair must share the helix angle magnitude and have opposite hands.

## Accepted ports

- `helical-gear.axis` → `helical-gear.axis`

## Parameters

- **`side`** — Where the driven gear sits relative to the anchor, in its local XY plane. One of right, left, up, down, or { angleDeg: N }.

## Parameters schema

| Parameter | Type | Default | Constraints |
| --- | --- | --- | --- |
| `side` | any | right | allowed: right, left, up, down |

## Kinematics

ω_driven = -ω_driver · (teeth_driver / teeth_driven). Same ratio as a spur mesh; the helix only affects visual geometry and engagement, not the tooth-count ratio.

## Layout

This connection computes the driven component position from the anchor.

## Example

```
connect H1.axis -> H2.axis with mech.helicalMesh {
  side: "right"
}
```