Choose the HMA150
You are already in that wheelbase ecosystem, you want a compact four-post install, three axes covers your use, and a first-party software stack with a single supplier is worth more to you than the extra axes.
Compare · MOZA
One shared spec.
Different kinematics.
The MOZA HMA150 and the PDK overlap on intent — high-precision sim racing motion — and on one notable specification, the 21-bit encoder. The kinematics underneath are a different arrangement entirely, and that is where the comparison actually lives.
Side by side
Where they meet and where they part.
| MOZA HMA150 | ARK PDK | |
|---|---|---|
| Architecture | Four-post arrangement | 6-DOF Stewart-Gough, six legs in parallel |
| Axes | 3-DOF: pitch, roll, heave | Six: surge, sway, heave, roll, pitch, yaw |
| Encoder | 21-bit | 21-bit absolute, 2,097,152 positions per revolution |
| Controller | 600 MHz processor, integrated 48 V | 1 kHz position commands (internal) · 8 kHz drive loop per motor · 3.3 kHz IK |
| Performance | 1 g and 300 mm/s at 250 kg; 0.45 g and 150 mm/s at 350 kg, as announced | 3 g peak, firmware safety limit, brief onset — payload figures not published |
| Software | First-party motion manager, game-agnostic | No first-party motion manager. Six-axis pose over UDP, so FlyPT Mover, SimHub or your own code drives it — none of them ours, none of them locked out |
| Price | $2,999, released 28 July 2026 | $4,899.99 PDK · $6,299.99 PDK Racer · $8,499.99 Ecosystem |
Figures in the other column are read from the manufacturer's published material, with source and retrieval date. Manufacturers revise specifications — if one here is out of date, tell us and it gets corrected. On the acceleration row: ours is 3 g peak, software-limited, describing a brief onset rather than a sustained load.
Sources: MOZA Racing — MOZA HMA150 Motion System (4 Actuators), us.mozaracing.com, retrieved 2026-09-13; MOZA Racing — MOZA Racing Debuts AI Coach and Motion Innovations at GDC 2026, mozaracing.com, retrieved 2026-09-13; MOZA Racing — MOZA Launches HMA150 Motion System (28 July 2026), mozaracing.com, retrieved 2026-09-13.
The real difference
Four posts give you three axes.
Six legs give you six.
A four-post arrangement raises and lowers corners. That produces pitch, roll and heave convincingly, and it cannot produce surge, sway or yaw at all — not less well, but not at all. Whether that matters depends entirely on what you are doing: for many racing applications three axes well executed is a good machine. For flight, for vestibular work, or for anything where the rear stepping out needs to arrive as rotation, the missing three are the whole point.
Which one you want
Both answers are defensible.
Choose the PDK
You need six axes — yaw, surge and sway as well — or you are working outside racing in flight, research or vestibular applications where those axes carry the information.
On the shared spec
Both use 21-bit encoders, and on that row there is nothing to choose between us. Encoder resolution is necessary and not sufficient; what differs is what sits between the encoder and the load.
Keep reading
What datasheets leave out
The method behind this page, applied to us before anyone else.
D-BOX
Another approach that is a different category rather than a different grade.
Sim racing
What each of the six axes actually gives you in a car.