Robot joints and actuation
smart servo: 1.8 N·m peak at 254:1, 97 rpm no-load.
Engineering inference
ROBOTIS
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.
AX-18ADevelopment boardPrice$126.39robotis.us · in stock
Buy at robotis.us Overview
Motor essentials
Facts about the complete product. Unknown values remain open design questions.
- Rated voltage
- 12 V
- No-load speed
- 97 RPM
- Gear reduction
- 254:1
- Encoder
- position sensing over 0–300°, 0.29° resolution
A good fit for
Guidance to help you shortlist. The basis is shown for each recommendation.
No-load speed, rated performance and stall limits describe different operating points. A stall specification is not a continuous operating rating.
3D model & CAD
3D model & CAD files
Generated from the datasheet's dimensioned drawing and measured against it. Download the STEP to check fit in your own enclosure.
- Envelope (L × W × H)
- 40 × 32 × 50 mm
- Verification
- generated
- Envelope complete
- Yes
Torque & control
Torque, speed and control
What the joint can deliver and how the controller talks to it.
- Type
- SMART_SERVO
- Gearbox
- engineering plastic stages 1–3, precious-metal stage 4 254:1
- No-load speed
- 97 rpm
- Encoder
- position sensing over 0–300°, 0.29° resolution
- Control
- TTL · position (joint mode, 0–300°), endless turn (wheel mode)
| Connector | Type |
|---|---|
| ttl | TTL 3-pin Molex (22-03-5035 header, 50-37-5033 housing), 21 AWG |
Rated torque is continuous; peak torque is short-duration. Values with two figures (e.g. 24/48 V) are per supply voltage.
Specifications
Motor performance
No-load, rated-load and stall figures retain their separate test conditions.
- Rated voltage
- 12 V
- No-load speed
- 97 RPM
Stall torque and current are not continuous ratings. Check the duty cycle and starting load when choosing the driver and power supply.
Thermal limits by level
Product operating conditions, chip ambient ratings, package case limits and junction maxima remain separate.
Motor body
- Product operating range
- -5 to 70 °C
Mechanical dimensions
Reported product dimensions may exclude protruding components. Unknown height does not establish a complete clearance envelope.
- Length
- 40 mm
- Width
- 32 mm
- Reported height / thickness
- 50 mm
Attached generated geometry is an approximate envelope. A generated outline does not establish an electrically verified PCB footprint.
Board connectors
| ID / type | Pins | Pitch | Notes |
|---|---|---|---|
| ttlTTL 3-pin Molex (22-03-5035 header, 50-37-5033 housing), 21 AWG | 3 | Unknown | — |
Complete structured record
Every available field, including details beyond the summaries. Null means the value has not been established.
Sourcing & files
Supplier offers
US / USD is the target market. Observed price and stock are separate from a delivery quote.
robotis.us
US · USD
$126.39Minimum quantity unknown
- Observed stock
- in stock
- Checked
- Oct 1, 2026, 09:50 PM UTC
- Delivery estimate
- Not quoted
Observed within the last 24 hours. Confirm the current supplier quote.
Visit supplier (opens in a new tab)Delivery depends on quantity, postal code and shipping method. A dispatch statement such as “ship today” is not an arrival estimate.
Design files and references
Each source keeps its own verification status. Confirm the part revision and file contents before using it in a design.
Datasheet (opens in a new tab)
Manufacturer reference
DYNAMIXEL AX-18A — product photo (robotis.us) (opens in a new tab)
Manufacturer reference
store og:image for the AX-18A page
STEP (generated from datasheet drawing) — link unavailable
Generated asset
cad_check passed
Generated envelope geometry may also exist for this record. It does not replace manufacturer CAD or a verified electrical land pattern.
Source evidence
Document provenance, retrieval dates and the field groups supported by each source.
Supports: spec.constraints.electrical.supply_voltage_max_v, spec.constraints.electrical.supply_voltage_min_v, spec.constraints.thermal.operating_temp_max_c, spec.constraints.thermal.operating_temp_min_c, spec.geometry.body_length_mm, spec.geometry.cad.bbox.height_mm, spec.geometry.cad.bbox.length_mm, spec.geometry.cad.bbox.width_mm, spec.geometry.cad.envelope_complete, spec.geometry.cad.mesh_path, spec.geometry.cad.step_path, spec.geometry.cad.verification, spec.geometry.dimensions.height_mm, spec.geometry.dimensions.length_mm, spec.geometry.dimensions.width_mm, spec.geometry.other.weight_g, spec.provides.actuator_type, spec.provides.control_interface, spec.provides.control_modes, spec.provides.encoder, spec.provides.features, spec.provides.gear_ratio, spec.provides.gear_type, spec.provides.integrated_driver, spec.provides.motor_type, spec.provides.no_load_speed_rpm, spec.provides.peak_torque_nm, spec.usage.connectors, spec.usage.pinout, spec.usage.pinout_complete, spec.usage.requirements.other.peak_current_a, spec.usage.requirements.rated_voltage_v
sha256 2e0be2232ba02e93c3dc65320deb9c8a5e74f3cb4b99e2a510269b92bc88841c
Supports: offers
FAQ
ROBOTIS DYNAMIXEL AX-18A questions
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.