# ROBOTIS DYNAMIXEL AX-18A

> ROBOTIS DYNAMIXEL AX-18A smart servo: coreless DC motor + 254:1 gearbox (plastic stages, metal final stage) + controller, 1.8 N·m stall at 12 V (2.2 A), 97 rpm no-load, 9–12 V (11.1 V recommended), 0–300° position control at 0.29° resolution or endless-turn wheel mode, TTL multidrop bus with 254 IDs, position / temperature / load / voltage feedback, 32 × 50 × 40 mm, 55.9 g.

- Manufacturer: ROBOTIS
- Part number: AX-18A
- Category: Actuators
- Canonical page: https://www.xirkit.io/products/robotis-dynamixel-ax-18a-491d
- Pinout: https://www.xirkit.io/products/robotis-dynamixel-ax-18a-491d/pinout
- Structured JSON: https://www.xirkit.io/products/robotis-dynamixel-ax-18a-491d/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Actuator type | smart_servo |
| Gearbox | engineering plastic stages 1–3, precious-metal stage 4 254:1 |
| Peak torque | 1.8 N·m |
| No-load speed | 97 rpm |
| Rated voltage | 12 V |
| Encoder | position sensing over 0–300°, 0.29° resolution |
| Control interface | TTL |
| Control modes | position (joint mode, 0–300°), endless turn (wheel mode) |
| Dimensions | 40 × 32 × 50 mm |
| Operating temperature | -5 to 70 °C |

## Pinout (3 pins, 0 with electrical limits)

| Pin | Position | Kind | Chip pad | Functions | VIH | VIL | VOH | VOL | IOH | IOL | 5 V tolerant |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| GND | MOLEX 22-03-5035 · TTL-1 | ground | — | ground | — | — | — | — | — | — | — |
| VDD | MOLEX 22-03-5035 · TTL-2 | power in | — | power_in | — | — | — | — | — | — | — |
| DATA | MOLEX 22-03-5035 · TTL-3 | signal | — | data | — | — | — | — | — | — | — |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| robotis.us | 126.39 USD | in_stock | 2026-10-01 | https://robotis.us/products/dynamixel-ax-18a |

## FAQ

**What voltage powers the ROBOTIS DYNAMIXEL AX-18A?**

Supply range 9–12 V.

**How much does the ROBOTIS DYNAMIXEL AX-18A cost?**

From $126.39 at robotis.us. Prices are observed unit prices before tax and shipping.

**What are the ROBOTIS DYNAMIXEL AX-18A dimensions?**

40 × 32 × 50 mm. A STEP model is available for enclosure fit checks.

**Where does this ROBOTIS DYNAMIXEL AX-18A data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [ROBOTIS DYNAMIXEL AX-18A datasheet](https://emanual.robotis.com/docs/en/dxl/ax/ax-18a/)
- [robotis.us listing](https://robotis.us/products/dynamixel-ax-18a)

## Part graph

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