ROTATRIX The trackball that merges pointing and 3D control.
Mouse, 3D orbit, and navigation in one device —
Experimental · Limited run
One device, many capabilities
Traditional trackballs treat the ball as a 2D input — at most, twist adds scrolling. There's a whole dimension being underused.
Rotatrix unlocks that extra dimension. Using custom hardware and firmware added to the Kensington SlimBlade Pro, it measures high-fidelity, continuous 3-axis rotation of the ball.
It's still your everyday trackball for pointing and scrolling — but in 3D apps, the same ball also gives you direct control of rotation, translation, and camera navigation.
Direct 1:1 rotation — rotate the ball in any axis and the object or camera follows. Roll, tilt, and twist in a single gesture, with no axis constraints.
Pan in X and Y, twist the ball for smooth, continuous zoom — no scroll wheel steps. It feels like pushing and pulling the model in depth.
Snap to any aligned view — faces, edges, corners, or any increment — with a single button. One control replaces dozens of keyboard shortcuts.
Hold a button or key to change what the ball does — mouse, pan and scroll, 3D rotation, translation, camera look, and more. One device for pointing, clicking, and navigating — no hand movement between devices.
Roll the ball to move and strafe, twist to turn — like walking through a space. When you need smooth travel over large distances, switch to rate mode. The trackball's infinite rotation allows silky-smooth adjustment.
Every mapping, binding, and behavior is user-configurable — per application, per mode. Tune axis filtering, sensitivity curves, and dominance to match how you work. Share and import profiles from other users.
“The more I refined it, the more natural it felt — like directly holding and turning a 3D model, or pushing and pulling it in space.”
I'm David Liu, a software engineer based in Brooklyn. I spent over a decade at Pinterest, most recently as a Senior Engineering Director leading the ML Platform team. I've also been doing CAD, 3D printing, and hardware projects for as long — always drawn to the intersection of software and physical things.
Rotatrix started as a weekend hack. I had switched to a trackball for ergonomics and got curious if it could do more than just point and scroll. I figured out how to capture the ball's full orientation with custom hardware and firmware, and tried it for CAD navigation. It felt so immediately natural that I kept building. Out of many experiments, this became the one I couldn't put down, so I formed Icebound Flame LLC and made it my full-time focus.
No crowdfunding, no preorders, no large production runs. Because Rotatrix is a modification of the Kensington SlimBlade Pro, a popular, well-built device, I can produce in small batches without minimum order quantities or upfront tooling costs. I buy components on demand, assemble and test units personally, and each batch funds itself. There's no scenario where low volume forces a shutdown — even at five units a month, the model works.
The software you receive works independently — if development ever stopped, your device and existing integrations keep functioning. I'm building the system around an openly shared protocol so third-party developers can build their own integrations without depending on me.
The modification is fully reversible. Every device ships with a one-year warranty. Full details at rotatrix.com/terms.
Native Autodesk Fusion plugin available now. More integrations are in development — sign up and tell me what tools you use to help prioritize what's next.
Windows 11 and macOS 15+ (Sequoia and above, Apple Silicon). Linux coming later.
Open output protocol — developers and users can build their own integrations for the apps and sites they care about. Applications can also send context back (like active tool, selection state, or viewport mode) enabling richer, context-aware control beyond simple hotkeys.
The core difference: a SpaceMouse is rate control — you push a puck to steer. Rotatrix is position control — the ball moves and the object follows, like holding and turning it in your hands. And because a full-size ball has far more travel than a puck that moves ~2mm, the input is inherently cleaner.
SpaceMouse — rate control
Rotatrix — position control
A SpaceMouse sits next to your mouse. That's two devices, two hand positions, and one hand locked to a dedicated controller that does nothing else. Rotatrix is your everyday pointing device with 3D navigation unlocked — mouse, scroll wheel, and 3D control in one hand, in one desk footprint. Your other hand stays on the keyboard for shortcuts or to modify the trackball mode.
SpaceMouse — hands moving between devices
Rotatrix — one hand, one device
The SpaceMouse Pro and Enterprise add physical buttons for common views — front, top, isometric. That works, but it's a fixed set of presets that you trigger by lifting your hand off the puck.
Rotatrix takes a different approach: as you rotate, the software can lock to straight-on, edge, and isometric views without having a bank of dedicated buttons — just rotate to the vicinity of the desired view and snap to it.
SpaceMouse — fixed preset buttons
Rotatrix — dynamic snap-to-angle
| Rotatrix | SpaceMouse | |
|---|---|---|
| Control model | Position — direct manipulation | Rate — push to steer |
| 3D navigation | Yes | Yes |
| Mouse pointer control | Yes | — |
| Scroll wheel and pan | Yes | — |
| Context-aware modes | Yes | — |
| Snap-to-angle | Dynamic — rotate to any view | Dedicated buttons, fixed presets |
| Keyboard access | Always — one hand on keyboard | Requires lifting off puck |
| Devices on desk | 1 | 2 |
If you need smooth simultaneous pan+zoom+orbit in a single gesture and you've tuned your SpaceMouse to the point where crosstalk doesn't bother you, SpaceMouse is still good at that specific thing.
If you want direct, intuitive 3D control that feels like physically handling your model, with your mouse and 3D navigation in one device, and you value clean intentional input over raw degrees of freedom — that's what Rotatrix is built for.
The SpaceMouse is a great device — I used one for years. Rotatrix takes a different approach: instead of a separate dedicated controller, your trackball becomes your 3D navigation device, regular mouse, and scroll wheel all in one. Your hand is literally on the thing you're rotating, so control feels direct and intuitive. And because everything is in one hand, the other is free for keyboard shortcuts — or just not needed.
A standard trackball can only send mouse input. Rotatrix adds a custom processing module that reads the ball's rotation in all axes and translates it into true 3D navigation — pan, orbit, zoom — with features like snap-to-angle that let you lock to a single axis of rotation cleanly. It's not a remapping trick; it's a fundamentally different control scheme.
A mouse gives you 2D input. Rotating a 3D object with a mouse means repeated click-and-drag gestures, constantly fighting the 2D constraint. A trackball has a third degree of freedom — the twist of the ball — that mice physically can't provide. Rotatrix captures that twist at high fidelity, giving you direct 3-axis orientation control in a single gesture.
A trackpad with gestures (pinch to zoom, two-finger swipe, shift+swipe) can give you roughly 5 degrees of freedom — but only one or two at a time, sequentially. Each gesture is a separate action with a separate hand shape. Rotatrix gives you 3 axes of continuous, simultaneous control in a single motion. That simultaneity is a fundamentally different feel — closer to holding and turning a physical object than issuing a sequence of commands.
It depends on what you're doing. The software has configurable dominant-axis filtering that you can tune to your preference. For full 3D rotation it feels natural with a small amount of axis filtering, and translation seems to benefit from a bit more. Intelligently selecting single-axis movement is an active area of development, and exactly the kind of thing I want early adopter feedback on. Your real-world workflows will shape how this evolves.
Unfortunately, no — a standard trackball doesn't have the data needed to derive 3D rotation. Rotatrix needs two optical sensors positioned at different points on the ball. That's what makes it possible to reconstruct full 3D orientation, not just XY position. The Kensington SlimBlade Pro has this dual-sensor design, which is pretty unique among trackballs. But the stock controller processes the dual sensor data into only an XY rotation OR scroll wheel increments (not smooth scrolling), and it does not report both movements simultaneously.
Rotatrix adds a custom control board that reads raw data from both sensors, host software to construct a continuous 3D orientation, and mode switching and remapping capabilities.
None. I purchase every SlimBlade Pro at retail and have no affiliation with Kensington. Rotatrix is an independent aftermarket modification of a retail product.
The modification voids Kensington's original warranty. That's why Rotatrix includes its own one-year warranty covering the full device — both the original SlimBlade Pro components and all modifications. Full details are at rotatrix.com/terms.
The host application and official integrations are closed source — that's what makes it sustainable to develop full-time over the long term. However, I'm building the system around an openly shared protocol that third-party developers can use to build their own integrations using the same APIs I use for official ones. The goal is a healthy ecosystem, not a walled garden.
The software you receive works independently — if development stopped, your device and existing integrations keep functioning. The open protocol means third-party developers can build new integrations without me. And the modification is always reversible. See Built to last for more on how Rotatrix is structured to avoid the risks of typical hardware projects.
Payment is handled through Stripe with standard card-level buyer protections. I only take orders for batches I have capacity to build, and I test every unit before it ships. See Built to last for more on how the project is structured.
US and Canada only for now. I'm collecting a waitlist for international orders — sign up and I'll reach out when shipping to your country is available.
For the first batch, I'm prioritizing based on location (US & Canada) and software compabitility. Sign up, indicate purchase interest, and I'll reach out with ordering details.
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I'm shipping a small number of early units and looking for people to help shape how Rotatrix evolves. If you're interested in trying it, let me know in the form — otherwise, sign up to follow along.