Pick a behavior. See what it replaces.
Six force functions, each printable into one flat piece of NdFeB. For every behavior: the mechanism, the real numbers, the force curve, and the industries using it. A conventional magnet has one curve; these are what happens when the curve becomes a design variable.
Precise self-alignment
Print a code on one face and its complement on the mating face. Only at exact registration does every north sit over a south — force peaks like a matched filter. Shift the parts and mismatched maxel pairs cancel, while the code gradient produces a restoring side-force that pushes the pair back to center. Engagement happens only in the last few millimetres, so parts self-seek without guides, pins or bezels.
Where it’s used: consumer electronics (the MagSafe/Qi2 ring is the shipping proof of magnetic self-alignment), robotics part-indexing, EV charge connectors.
Magnetic spring & standoff
Superimpose two pattern scales: a coarse code that attracts at range and a fine code that repels up close. The pair pulls itself in, then stiffens against contact and floats at a designed equilibrium gap — a contactless spring and vibration isolator with no fatigue and no creep. Earnshaw’s theorem still applies: the equilibrium is unstable sideways, so every real spring pair runs on a shaft or pin.
Where it’s used: industrial fixtures, vibration standoffs, soft-close assists in furniture hardware.
Twist-release & slide-release
The code is laid out so that a specific motion — a 20° twist, a 6 mm slide — drives the pair from perfect correlation to perfect ANTI-correlation. Aligned, it grips harder than a plain magnet of its size; through the release motion the same faces actively repel and eject each other. A latch, a detent and an ejector spring in a single passive part. This is the behavior NASA flew.
Where it’s used: aerospace release mechanisms (NASA Prandtl-M — the one verified customer), tool-less device mounts, quick-change end-of-arm tooling.
Coded pairs & keying
Codes borrowed from radar: a Barker sequence autocorrelates sharply — strong force only when the right code meets its complement at the right alignment. A different code produces near-zero net force at every offset. Magnets acquire identity: connectors that refuse the wrong socket, fixtures that reject the wrong part, interlocks that can’t be defeated with a fridge magnet. Rejection is analog — strong discrimination, not literally zero (published rejection ratios: none — a gap we flag).
Where it’s used: coded safety interlocks (a regulated, shipping category), poka-yoke assembly, anti-counterfeit closures, sterile-tooling concepts.
Attenuated & shaped field
In a fine pole pattern every maxel’s flux closes through its neighbors a millimetre away instead of ballooning into space. The far field can be engineered toward zero while contact force stays high. The result is a magnet that grips like a vice but doesn’t wipe hotel keys, tug compasses, disturb Hall sensors or collect swarf — the property that makes magnets acceptable inside dense electronics.
Where it’s used: consumer electronics everywhere a magnet sits near a sensor, magnetically clean spacecraft (documented problem; coded insertion illustrative), implant-adjacent hardware.
Shear & torque transmission
Plain magnets resist separation; sideways they mostly rely on friction. A coded pair has true magnetic shear stiffness — displace it laterally or rotationally and correlation forces pull it back. That transmits force and torque across an air gap: couplings and magnetic gears with built-in overload slip and zero mechanical wear, detents with engineered click-stops at 90° or 30°.
Where it’s used: magnetic couplings and quick-change tooling, end-of-arm tooling, rotary detents in product interfaces.
Mechanism details, correlation math, Halbach comparison: the companion encyclopedia goes deep on every one of these.
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