6 × 750 W AC servos
Your choice: AASD15A with Step/Dir, or StepperOnline A6 EtherCAT with holding brake — more compact and fully synchronised.
In the field since 2024 · Third generation
MAKE 3
The 6-DOF rig that has been proving itself for years.
Six 750 W servos on 1:50 planetary gearboxes, 180 mm cranks and a laser-cut steel hexapod — as a kit, with Step/Dir or EtherCAT drives.
6degrees of freedom
6×750 WAC servos
1:50planetary gearboxes
±175 mmsurge · sway · heave
115 kgrig weight
MK3 — Make 3
Rotary actuators. Nothing to wear out.
The MK3 is a Stewart platform with rotary actuators: six servo cranks swing on 1:50 planetary gearboxes and push the platform through 459 mm rods. Surge, sway, heave, roll, pitch and yaw are available independently and in any combination.
No ball screws, no linear guides, no wear parts in the force path — the gearbox carries the load, the rod ends take the angles. That is why the rigs built in 2024 are still running today.
- Crank circle R 465 mm, platform circle R 391 mm — a low, stable rig
- Deck only 720 mm above the floor: easy to step into, fits under a low ceiling
- MK3 and MK3+EC presets with live 3D view in the Motion4Sim Dashboard
Engineering
Industrial parts, built to be built.
Standard industrial drive technology, laser-cut steel and a kit you can assemble yourself.
1:50 planetary gearboxes
CNC-quality planetary gearboxes, 90 mm frame, 8 arcmin backlash. They carry the load — there is nothing in the force path that wears.
180 mm crank, 459 mm rod
Rotary kinematics with M16 rod ends. Short lever, high force, and the full stroke inside half a servo turn.
Laser-cut steel
Steel in 2, 3 and 5 mm, bolted base boxes and a triangular top frame — optionally powder-coated matte black.
Motion4Sim controller
Included in the kit, with handheld unit. The Dashboard carries the MK3 preset with a live 3D view; Pro+ adds the EtherCAT master.
A kit, not a mystery
Step-by-step video documentation of every assembly phase, support on Discord — and the demanding jobs available as a service.
Six degrees of freedom
Every axis. Fully independent.
Rendered from the CAD model with the controller's own kinematics — each clip shows one axis, the camera flies around the rig.
Surge
±175 mm
Forwards and backwards — acceleration and braking.
Sway
±175 mm
Sideways — lateral forces in corners.
Heave
±175 mm
Up and down — kerbs, bumps and crests.
Roll
±27°
Tilt about the longitudinal axis — body roll and banking.
Pitch
±27°
Nose up and down — dive under braking, squat under power.
Yaw
±35°
Rotation about the vertical axis — slides, drifts and traction loss.
Working envelope on a single axis. The geometry alone would allow more (surge −267/+318 mm, sway ±276 mm, heave −196/+180 mm, roll ±27°, pitch −27/+31°, yaw ±41°) — the 3D viewer below shows both. In combined motion the controller keeps the platform inside the safe workspace.
Interactive
Drive it yourself.
The real CAD model with the real kinematics, computed live in your browser. Move the sliders — every crank, rod and joint follows.
Loading CAD model 0 %
Drag to orbit · scroll or pinch to zoom · right-drag to pan
Dimensions
How much space do you need?
Measured directly on the CAD model — retracted, neutral and fully extended, next to a 1.80 m person.
Footprint (base)–
Deck height–
Overall height–
Overall length–
Floor space needed–
All values in millimetres, measured on the model, floor = underside of the levelling feet. The cockpit shown is an example and is not part of the kit; the length given for it is a practical figure to the front edge of the pedal plate, not a measurement off this model.
Gallery
Every angle.
In the field
Real rigs.
Built MK3 rigs — at customers and in our own workshop.
115 kgrig weight without cockpit
150 kgpayload incl. cockpit and driver
600 mm/splatform speed
4.5 kWconnected load, ~400 W in use
Two drives
Step/Dir or EtherCAT.
Same mechanics, same kinematics, same motion range — the difference is the drive. The EtherCAT servos are more compact and, above all, have a holding brake.
| Feature | MK3 · AASD15 | MK3 · EtherCAT (Pro+) |
|---|---|---|
| Servo motor | 6 × 750 W AC servo, AASD15A drive | 6 × 750 W StepperOnline A6, A6-750EC drive |
| Control | Step/Dir | EtherCAT, synchronised |
| Encoder | 10 000 counts/rev | 17 bit (131 072 counts/rev) |
| Holding brake | none — without power the platform drops like a stone | yes, on all six axes, 24 V, synchronised release |
| Motor size | 80 mm frame | 80 mm frame, shorter overall |
| Power distribution | Wiring set from the kit | Motion4Safe Power Hub: 12/24 V, AC filter, overcurrent protection, energy monitoring |
| Controller licence | Basic | PRO+ — EtherCAT master, dual LAN |
| Gearbox | 6 × planetary gearbox 1:50, 90 mm frame, 8 arcmin (identical on both) | |
| Motion range | identical — the mechanics are the same | |
On the EtherCAT variant all six axes have holding brakes: cut the power and the platform stays exactly where it is. The Step/Dir variant has none — and it does not sink gently, it drops like a stone onto the bottom stop. Never reach underneath, and never leave anything under the platform; a pure sine wave UPS of about 2000 W bridges a mains failure. Motors and gearboxes are not part of the kit; we name the exact types and check your order. The EtherCAT variant requires the MK3 PLUS upgrade kit and the StepperOnline A6 servos.
Technical data
Specifications.
Motion
- Type
- 6-DOF Stewart platform, rotary actuators
- Surge
- ±175 mm
- Sway
- ±175 mm
- Heave
- ±175 mm
- Roll
- ±27°
- Pitch
- ±27°
- Yaw
- ±35°
- Speed
- up to 600 mm/s
- Resolution
- 0.005 mm (theoretical)
Drive
- Actuators
- 6 × rotary, crank 180 mm, rod 459 mm
- Servo motors
- 6 × 750 W AC servo (not included)
- Gearbox
- 6 × planetary 1:50, 90 mm frame, 8 arcmin
- Servo swing
- ±90°
- Payload
- 150 kg incl. cockpit and driver
- Power
- 230 V socket, 4.5 kW connected load, ~400 W in use
- Joints
- M16 rod ends, industrial bearings, taper bushings
Geometry & dimensions
- Crank circle
- R 465 mm
- Platform joint circle
- R 391 mm
- Footprint (base)
- 1151 × 1017 mm
- Top frame
- 810 × 736 mm
- Deck height
- 545 / 720 / 895 mm (retracted / neutral / extended)
- Weight
- approx. 115 kg without cockpit
- Cockpit mount
- Adapter 520–680 mm rail spacing, M8 pattern
Structure & electronics
- Material
- Laser-cut steel, 2 / 3 / 5 mm
- Finish
- blank, or powder-coated matte black (option)
- Base
- Bolted steel boxes, 3D-printed corner covers, levelling feet
- Controller
- Motion4Sim 6-servo controller incl. handheld unit
- Cabinet
- none — servo drives sit in the base
- Lighting
- Red LED strip in the base (included)
- Software
- Motion4Sim Dashboard, SimTools, FlyPT Mover, Sim Racing Studio, SimHub
Notes
- Kit The MK3 is supplied as an unassembled kit. Assembly requires technical skill; mains connection and commissioning must follow local regulations.
- Not included Servo motors, gearboxes, PC and cockpit are sourced separately — we name the exact types and check your order.
- Motion range Single-axis working envelope. The geometry allows more; the controller keeps combined motion inside the safe workspace.
- Floor No floor anchoring needed under normal load. The rig is quiet enough for use at home.
- Your part of the work About 390 threads to tap, drilling the gearbox mounting holes to 8.4 mm, wiring and crimping — each of these is also available as a service (see prices).
Controller & software
Plug in. Pick a sim. Go.
The MK3 runs on the Motion4Sim controller, which is part of the kit. The Dashboard ships with MK3 and MK3+EC presets — geometry, actuators and limits are already set, and the 3D view shows your rig live.
Motion data comes from the cueing software you already use.
SimToolsFlyPT MoverSim Racing StudioSimHub
FAQ
Questions & answers.
How much floor space does the MK3 need?
The base covers 1151 × 1017 mm. With every axis at its limit the platform sweeps a little more — the dimension drawings above show the exact sizes in every position.
Which cockpit can I mount?
Aluminium profile cockpits with 520 to 680 mm rail spacing bolt straight onto the adapter plates. The cockpit itself is not part of the kit.
How heavy can driver and cockpit be?
150 kg on the platform — cockpit, wheel base, seat and driver together.
How much work is the assembly?
Mostly bolting parts together, plus about 390 threads to tap and the electrical wiring. Thread tapping, powder coating, pre-assembled bearing blocks and ready-made cable sets are all available as options.
Which motors do I need?
Six 750 W AC servos — either AASD15A with Step/Dir, or StepperOnline A6 EtherCAT with brake for the Pro+ variant — plus six 1:50 planetary gearboxes, 90 mm frame. We send the links and check your order before you buy.
How loud is the MK3?
The 750 W servos are passively cooled, so there is no fan noise. What you hear is the gearboxes and the rig itself — quiet enough for a flat.
What happens when the power goes off?
With the EtherCAT variant all six axes have holding brakes: the platform stays exactly where it is. The Step/Dir variant has no brakes — it does not settle, it drops, straight down onto the bottom stop, in a fraction of a second. So never reach underneath and never leave anything under the platform. A UPS takes care of this: a pure sine wave unit of around 2000 W carries the rig through a mains failure so you can bring it down under control. Pure sine matters — the stepped waveform of cheaper units upsets the servo drives.
Prices
What it costs.
The kit is the complete steel structure with all the electronics. Servos and gearboxes are not included — you source those yourself, and we name the exact types.
MK3
Step/Dir drive, AASD15 servos
from $3,760.83
without servos and gearboxes
MK3 PLUS
EtherCAT with brakes, Motion4Safe
from $4,759.83
without servos and gearboxes
Not included: 6 servos, 6 planetary gearboxes 1:50, control PC and cockpit. Thread tapping, powder coating and pre-assembly are available as options. Lead time 10–20 days, plus 10–14 days for the powder-coated version. Shipping, customs and taxes come on top — we are happy to quote your exact configuration.
Interested in the MK3?
Tell us about your set-up — we will get back to you with a configuration and a shipping quote.