Name: HashBrake/apple-hardware-design
Author: Community

Apple Hardware Design

How Apple's Industrial Design team makes objects feel inevitable, distilled from Apple's own case-maker dimensional drawings, the Accessory Design Guidelines (R32, Oct 2026), the HIG, Apple's environmental reports, Apple ML Research's robot-motion papers, Apple patents, teardowns, and twenty-five years of Ive/Apple interviews. Everything here is translated for someone building robots and other hardware in CAD.

The through-line: an Apple object reads as one thing. It is a single primitive made of one honest material, and its manufacturing process determines its shape. Every visible surface is curvature-continuous, every seam is deliberate, and every detail gets care in proportion to how often a hand touches it. Everything that isn't the product's job has been removed, or is hidden until it's needed.

"We try to develop products that seem somehow inevitable." — Jony Ive

"Just because something is uncluttered doesn't mean it's good. It can be cold, it can be soulless." — Ive, 2025

How to work

Pick the mode from the request:

Design mode ("design / restyle / make this Apple-like"). Output a design spec before any CAD. The spec covers:
- the primitive and proportions
- the edge family and radius values
- the seam map
- CMF, including the manufacturing process for each visible part
- controls, lights and docking
- service strategy
Then give the CAD steps or code. Offer 3–5 parametric variants of the key proportion and say which one you'd pick and why (Apple builds prototypes every 0.1″ and lives with them).
Fast path (a narrow ask: "fillet this cover", "what radius here", "colour for this part"). Answer it directly with the number, the CAD option and the one rule behind it. No spec, no variants, unless the user asks for more.
Review mode (a screenshot, render, STEP or description). Run the Review checklist at the end. Score each item 0–2 and mark N/A items. Report the score as a percentage of the applicable items. List fixes ranked by visual impact, each with a concrete number ("plan corner R8 tangent arc → continuous corner, R_core 14, extent 19 mm").
- From a single render or screenshot:
  - Estimate radii and gaps by scaling against a known dimension (overall size, a USB-C port 8.4 × 2.6 mm, a screw head), and say they are estimates.
  - Judge continuity from the highlights. A highlight that snaps or changes width where a fillet meets a flat means G1.
  - Then ask for the evidence that settles the rest: zebra stripes on every hero transition, a curvature comb on the main section, a plan view, and a gradient-softbox 3/4 render (references/cad-workflow.md §2).
Code mode (CadQuery / build123d / OpenSCAD / FeatureScript). Use scripts/apple_corner.py for plan outlines. Follow the kernel workarounds in references/cad-workflow.md §1, because OCC fillets are G1-only.

Always name the CAD tool's real option ("SolidWorks Fillet → Curvature continuous", "Fusion Continuity: G2 + Setback corners", "Onshape cross-section: Curvature"). If the user hasn't said which tool, ask, or give the options for all three.

Safety and standards override aesthetics. Design them in beautifully; never design them out. See §21 for the full list. The short version:

E-stops follow ISO 13850 / IEC 60204-1: red actuator on a yellow ground, reachable, never hidden.
Required nameplates, warning labels and warning lights stay visible.
Pinch and shear guarding, touch temperature, IP sealing and RF performance come first.

1. Inevitability: reduce before you refine

The test: every surface, line, feature and color needs a functional or manufacturing reason. If it needs a story to justify it, delete it.
One hero gesture per product. Cut ports, LEDs, colors, textures and part lines until removing one more would break the product. Focus is "saying no to something that with every bone in your body you think is a phenomenal idea."
Simplicity means resolved complexity, not a blank box. Consolidate parts and functions; don't hide them behind a bigger cover. A cold, featureless slab is the failure mode.
Familiar archetypes beat sci-fi.
- Apple's robot research chose a lamp because people already read a head, a neck and a gaze in it.
- The Watch was meant to be "strangely familiar."
- Avoid "robot face" theatrics, chrome-and-LED spectacle and automotive gloss.
Do the care where hands go. Ive spent effort on a packaging pull tab because "millions of people would engage with this little tab." On a robot the touch points are:
- the handle or lift point
- the e-stop
- the dock interface
- the service hatch
- the gripper pads
- the first touch out of the box

2. Primitive & proportion

Reduce each major module to one dominant primitive: a square slab (Mac mini, Studio, Apple TV), a cylinder (Mac Pro 2013, HomePod), a truncated sphere (HomePod mini), a dome (iMac G4 base, HomeView), or a disc (AirTag, MagSafe). Features are cut into or inlaid on that volume, never bolted on as bosses.
Use simple integer ratios, not φ. The golden-ratio story is a debunked myth. Apple's real proportions:

Product Height : side
Apple TV 1 : 3 (93.24² × 31.00 mm)
Mac mini 2 : 5 (127² × 50)
Mac Studio ≈ 1 : 2 (197² × 95)

Square footprints are common.
Symmetry and shared axes. Center features on the primary axes. Holes, buttons and lenses share a centerline or a tangent, and their pitches repeat (the iPhone 16 Pro camera grid uses 3 × 16.20, 2 × 8.85 mm). Margins to the edge are equal. Center mathematically, then offset optically where it looks wrong.
Mass stays low; the payload stays light. The iMac G4 has a heavy dome carrying the electronics and a gleaming, thin, counterbalanced arm holding a light screen. This is the most robot-relevant Apple form.
Concentrate thickness in one honest place. The iPhone Air puts all its depth into a full-width plateau so everything else can be 5.64 mm thick. A robot's bulk (compute, battery, actuators) should live in one deliberate volume, not spread as lumps.

3. Corners: continuous curvature, never a plain fillet

Apple dimensions every small feature as a radius, but the body corner is given as a spline-point table on its own drawings. It is deliberately not an arc. A tangent arc (G1) jumps from 0 to 1/R curvature, which shows as a highlight snap. Ive called these "unresolved tangency breaks."

G2 or better on every A-surface transition that light can run across. G1 is acceptable only for breaks under ~0.3 mm or on hidden surfaces.
Measured from Apple's drawings: the curvature ramps up from zero to its tightest at the 45° apex, then back down.
- That apex radius is the visual radius R you read by eye.
- Extent E ≈ 1.41 × R (E is the distance from the virtual sharp corner to where the curve leaves the flat; the measured range is 1.35–1.5, and iPhone runs tighter at ≈1.2).
- It fits one exact quintic Bézier per corner, within 0.28% of E (see the script).
- Figma's "iOS" smoothing (60%) looks close but overshoots its curvature by ~25%.
Corner size by object:

Object R_core
Hand-held ≈ 25% of the short side
Desktop object ≈ 20%
Large flat panel (iPad-like) ≈ 8%
Do not use one superellipse for the whole outline. It has no true flats, and Apple products have long, true flats. Superellipse corners joined to lines are G2, but they run longer than Apple's (E/R ≈ 1.8 at n=3, 2.5 at n=4, 3.3 at n=5, vs Apple's 1.41). Don't push n up thinking it's "more Apple".
Generate it:
```
python3 scripts/apple_corner.py --w 120 --h 80 --r 16 --fmt build123d   # or cadquery
python3 scripts/apple_corner.py --w 120 --h 80 --r 16 --fmt ctrl        # control points for interactive CAD
python3 scripts/apple_corner.py --w 120 --h 80 --r 16 --fmt check       # G1/G2 verdict (try --model arc to compare)
python3 scripts/apple_corner.py --w 120 --h 80 --r 16 --offset 3 --fmt csv   # concentric inner outline
```
- Each corner is one exact degree-5 Bézier. Its first three control points lie on one flat and its last three on the other, so the joint has zero curvature: G2 by construction.
- The build123d / cadquery output is 4 Lines plus 4 Beziers. It was tested in OCC: the solid is valid, the curvature is 0 at the joints, there are no inflections, and the apex hits the requested R exactly. It exports clean STEP.
- Interactive CAD: use --fmt ctrl and draw each corner as a degree-5 control-point spline through the 6 points. Then join the corners with lines.
  - SolidWorks: Style Spline → Bézier, degree 5.
  - Fusion: Control Point Spline, degree 5.
  - Onshape: Control point spline, degree 5.
- Never fit one spline through the whole outline: you lose the true flats.
- Verify with zebra stripes.
- Concentric offsets must stay below the visual R, or the inner corner cusps. For a larger inset, generate a new, smaller corner instead.

4. Edges: one family, one size

Pick ONE edge family for the whole product.

Family	Apple precedent	Recipe	When
Flat band + G2 roll (default)	iPhone 12–17, iPad Pro	Side is 40–60% true flat, then a G2 roll of R ≈ 0.25–0.35 × thickness (iPhone 16: flat ±1.62 of 7.81 mm, roll R ≈ 1.8–2.8)	Precise, modern
Pillowed	iPhone 6–11, AirPods, HomePod mini	Continuous G2/G3 section, no side flats	Friendly, hand-held, soft
Soft break on a machined slab	MacBook, Mac mini, Studio	Big flats, uniform 0.3–1.0 mm break	Machined metal shells
Flat + diamond-cut chamfer	iPhone 5	45° bright chamfer of 0.3–0.6 mm on a matte body; identical all round	One jewel line on anodized aluminum
Taper / knife edge	MacBook Air wedge	Thickness varies	Only if the taper hides real thickness (Apple abandoned it in 2022)

Give every visible break the same size. Never mix a chamfered lid with pillowed sides.
Big faces are truly flat. Apple doesn't crown panels; all the softness lives in the edge transitions.
No anodized edge sharper than R0.3 / C0.2 (R0.5 preferred). On the iPhone 17 Pro, sharp plateau edges chipped ("scratchgate"). Handled and grounded edges get more radius. Robot surfaces that may touch people need even larger radii (see §21, ISO/TS 15066).

5. Concentricity

R_inner = R_outer − offset, sharing one center. For continuous corners, offset the whole curve rather than picking a new radius. This applies to:
- display and sensor windows in the shell
- button caps in their pockets
- lids in frames
- perforation fields in panels
- joint shrouds around axes
If R_outer − offset ≤ 0, shrink the inner corner to a small break or widen the border. Never choose an arbitrary radius.
Apple's 2025 design system formalizes three shape types (fixed, capsule = height/2, concentric) and warns against corners that look "pinched or flared."

6. Seams, gaps, flushness

Parting lines are designed lines. Put them on a primary axis, symmetric, at constant width, and aligned to other features. Place them at a change of material or direction (glass→metal, roll→flat, a tangent edge). Never mid-face, never mid-fillet. iPhone antenna lines are symmetric, color-matched and honest.
Minimize part count. One unibody or extrusion where loads allow. Apple's unibody replaced many parts "with just one part."
Targets (Apple publishes none; these are premium-CE practice):

Item Machined Molded
Visible gap 0.10–0.20 mm 0.15–0.30 mm
Gap variation ≤ ±0.05 ≤ ±0.05
Flush ±0.05 ±0.10
Button proud 0.3–0.6 mm, same edge break as the body same
Make it flush, or make it a deliberate step (≥ 0.5 mm, or a designed reveal 0.3–0.6 mm wide). Never 0.1 mm "almost flush."
Apple sorted iPhone 5 back panels into 725 size bins and matched them by camera. Even gaps are a manufacturing system, not a hope. Locate every skin from the internal chassis, and float skins on a pin plus a slot. Stack-check every visible gap.
Scale gaps with size, temperature and load. Phone-scale numbers don't survive on a 300–800 mm robot shell: aluminum grows ≈0.46 mm over 500 mm at ΔT 40 K, and links flex under payload.
- Budget each gap from a stack-up of tolerance, thermal growth and deflection. A useful start is 0.2 mm + 0.5 mm per metre of panel length (practice).
- On long seams, prefer a designed reveal (0.5–1.0 mm), which hides that variation, to a hairline that rubs and clicks.

7. Material is the structure (CMF)

One primary material, used structurally. The shell is the chassis, the heat spreader, and often the antenna ground. Examples:
- iPhone 17 Pro: forged 7000-series aluminum unibody with a vapor chamber laser-welded inside.
- Mac Pro: a stainless frame whose polished handles and feet are the structure.
Don't put a cosmetic skin over a separate frame.
Truth to materials. Machined aluminum looks machined; plastic looks like good plastic (Apple: the iPhone 5c was "unapologetically plastic"). Never paint plastic to fake metal. No fake vents, fake screws, decals or faux textures.
Physics picks the material. Apple dropped titanium for aluminum on the 17 Pro for thermals and weight. Titanium is a premium signal for small, high-touch parts, not a default.
Default finish:
- Fine bead blast (glass/zirconia, ≈100–170 mesh) plus MIL-A-8625 Type II anodize, 10–15 µm.
- Satin, Ra ≈ 0.4–1.0 µm.
- Anodize all mating parts in one batch.
Accents:
- One polished "jewel" per product: a handle, a chamfer, a logo or a lens ring. A diamond-cut chamfer is cut after anodizing, then optionally re-anodized clear.
- Polished stainless for structural lift points and joints, against matte bodies.
- FKM/LSR (Shore 50–70A) for grip pads and bumpers.
- 3D knit or acoustic mesh for speakers, mics and human-contact soft covers, with the seam on the hidden face.
Durability before story. FineWoven scratched and stained, and it died. Abrasion-test any "sustainable" or unusual material.
Glass/PMMA dead-front for faces and sensor windows: back-inked black, anti-glare, 0.2 mm edge chamfer.
Full recipes, alloys, prototype paint specs (satin clear 20–30 GU @ 60°) and inspection methods are in → references/cmf-materials.md.

8. Color

Body: one neutral. Silver ≈ #E3E4E5, Space Gray ≈ #7D7E82, Space Black ≈ #2E2D2F, Midnight ≈ #2E3641 (blue-black), Starlight ≈ #E8DFD3. These are estimates; Apple publishes none.
At most one hero accent, on one functional element. Watch Ultra puts International Orange on the Action button only; the iPhone 17 Pro has Cosmic Orange. On a robot, use it for the primary action, the status ring or the gripper tips. Never on the e-stop, which keeps its regulated red/yellow.
Consumer and home variants: two-tone, with a pastel front and a saturated back (iMac 2021). Peripherals, cables and the dock are color-matched.
Cables, overmolds and docks match the body, or they are all black. Internals visible through gaps are black or dark gray.
ΔE00 ≤ 1.0 between mating parts. Check metal against paint or plastic under D65 and LED light.
Pro / industrial robot: silver or space gray, matte. Home / companion robot: soft, slightly desaturated colors, possibly fabric. Never more than two body colors.

9. Openings: vents, perforations, ports, windows

Vents follow exactly one of three strategies:

Hidden: under the base (Mac mini, Studio), in a hinge gap (MacBook Pro exhaust), behind the stand (iMac), or along the underside (Vision Pro).
Texture: a field of identical, precise perforations or mesh (Studio's 4,000+ holes, HomePod).
Celebrated structure: a lattice that is the heatsink (Mac Pro / XDR, hemispheres milled from both faces).

Never use visible louvers, mixed slot sizes, exposed fin stacks or visible fan blades. For IPX3–X5 rain or spray, put the louvers and labyrinth baffles behind the clean perforation or slot face, add a drain path, and fit a hidden membrane vent (Gore-type). The visible face stays a pattern.

Airflow runs in a straight line: bottom → back, front → back, or bottom → top like a chimney. Going fanless is a design win; make the shell the heatsink first.
- Above ≈15–25 W of sustained compute in a small shell (Jetson-class at 30–100 W), plan a quiet fan from day one. Use a hidden intake and a large, slow impeller, and decide this early.
Perforation rules:
- One hole size per product.
- A strict hex or square grid, clipped by an offset of the panel outline (field corners concentric with the panel). Never randomly truncated.
- ≈0.5 mm clearance around mic/IR holes.
Ports:
- Grouped in one strip, mostly at the back; high-use ports in front.
- Obround openings with full-radius ends, machined straight into the shell, with no plastic insert.
- A flat land around each port. Size openings for third-party overmolds (USB-C opening ≥ 12.35 × 6.50 mm, ideally 12.45 × 6.60).
Sensor and camera windows (straight from Apple's camera-trim rules):
- Never intrude into the FOV cone under the worst-case tolerance stack.
- Chamfer the trim next to the lens.
- Use semi-gloss black trim; matte scatters stray light into the lens.
- Gather every sensor onto one raised plateau with two relief tiers (plateau, then lens rings), in body material and color, never a stuck-on black box. iPhone 16 Pro tiers: 2.05 mm, then 4.28 mm.
- Hide IR emitters, ToF sensors and fiducials behind an IR-transmissive window that looks smooth to the eye. Behind the window, put an opaque baffle between emitter and receiver so light doesn't cross-talk through the window.
- Recessed lips catch dust and water. Give every window a cleaning path (an open edge on one side, a drain) and an easy wipe angle.
Protect glass with geometry. Any glass or window sits ≥ 0.85 mm (ideally 1.0) below a surrounding lip, so a flat surface can't touch it from any orientation. This is Apple's case rule and the Watch Ultra's raised titanium lip.

10. Controls & touch points

Almost no buttons. One primary control with one essential function. Put a control out of sight only where it's still easy to use: the Mac mini's underside power button and the Magic Mouse's bottom port are Apple's own cautionary tales.
Sealed surface + force sensor + synthesized click is Apple's signature. Examples: Force Touch trackpad, iPhone 7 Home button, Digital Crown detents, AirPods stem, Camera Control. On a robot this gives IP-friendly controls with no moving seams.
Premium button stack (Camera Control):
- flush jewel cap (sapphire/glass) in a thin color-matched metal ring
- three layers of input: touch/slide → light press → click
- flush height calibrated per unit
- cap flatness < 25 µm, stiffness ≈ 90 gf/mm, preload ≤ 45 gf
- the opening is "large with smooth edges and a wide angle," and works with long nails
Dials (Digital Crown):
- fine straight knurl (~0.3 mm pitch), slightly proud, set into a guard
- press on the axis
- detents are haptic and tied to software steps
- every turn gives visual feedback, at a rate that follows turn speed
Specify the feel and sound of every actuation: short, damped, low-frequency. No rattles, no creaky snaps. Isolate haptic and motor vibration from cameras, IMUs and mics.
Ergonomics: design for the 5th-percentile hand up to the 95th (ANSUR II / CAESAR). Every gesture needs a physical alternative.
A rugged variant follows the Watch Ultra recipe: same base form, plus raised metal guards around the glass and controls, thicker gauges, one high-visibility accent, and symmetric exposed Torx screws. Honest fasteners are allowed when the product is tough.

11. Light & indication

One status light, invisible until lit. Laser micro-perforations (≈30–80 µm holes through a wall thinned to 0.3–0.4 mm) or a smoked dead-front (5–15% transmission).
Apple's keyboard rule: "shall not incorporate any other status LEDs" beyond Caps Lock, connection and battery.
Palette: white = system/pairing, amber = charging/attention, green = done. Very few states, readable at a glance, never decoded. Breathing for sleep or idle, solid for active.
Never decorative lighting. No RGB, no LED bars, no Glyph patterns. Light that shows up when it's needed (the 2013 Mac Pro lit its port labels when you turned it) is very Apple. A light ring is acceptable only if it is the primary form, like the HomePod top.
Never color alone: pair it with shape, motion or sound.
Flashing: stay well under 3 flashes per second (the photosensitivity limit) and support dimming. A slow "breathing" sleep light (~0.2 Hz, smooth) is fine. HIG's 0.2 Hz warning is about large moving visuals in visionOS, not LEDs.
Functional safety lights are not decoration, and they are required where standards ask for them. Examples: ISO 3691-4 warning lights and sounds on mobile robots, IEC 60073 / IEC 60204-1 indicator colors, collaborative-mode indicators.
- Integrate them as designed light lines or rings in the primary form, still invisible until lit.
- Keep the regulated colors and meanings.

12. Docking, charging, attachment

Charging must not disable or embarrass the product. Design the charging state; the Magic Mouse is the anti-pattern.
The MagSafe pattern for docks and tool changers:
- a magnet ring for capture, plus one offset magnet for rotational keying
- inductive power or recessed pogo pins in the center
- NFC/ID for the accessory
- self-alignment within ≈1.5 mm
- pull-off force ~1–1.3 kgf for a phone-scale part (scale it up)
- no "false attach": it holds only where it can charge
- Figure 03 charges wirelessly through its feet, which is exactly the right instinct.
Covers and lids:
- Watch-band slide-lock (slide into an undercut channel, hidden spring latch underneath; spec 5–20 kgf lateral, ≥ 20 kgf pull) for actuator and joint covers.
- AirPods over-center + magnets (bistable, a crisp snap, a damped landing, no latch) for hatches.
- Magnetic doors for battery and service, unless a standard requires a tool to open them (many battery and electrical-access rules do), and kept well away from magnetometers and IMUs. Exposed magnets collect ferrous debris on shop floors.
A flat facet on a round part does four jobs (dock, charge, anti-roll, orientation), as on Apple Pencil.
One cable, color-matched, braided, often magnetic or breakaway (MagSafe 3). Move secondary functions into the brick: the iMac put Ethernet in its power adapter.

13. Mechanisms: weightless, holds where you leave it

Counterbalance everything that moves by hand. Examples: iMac G4 neck, Pro Stand, Studio Display, HomeView hinge, the one-finger MacBook clutch hinge. It moves with one finger and stays put. No visible springs, knobs or cranks.
Holding spec (Apple's mount rule): within 2° of where the user left it, after 4 h and after vibration.
Joints are concentric shrouds with a constant 0.3–0.5 mm rotating gap, one radius family across all joints, and the seals hidden in a reveal. Polished stainless or machined joints against matte blasted bodies.
- Check every moving gap for pinch, shear and hair or skin snag (ISO 13854: keep it under ~4 mm, or open it past the 25 mm finger gap; no scissor edges).
- Check every moving gap for its contamination path too.
AirPods Max is the mechanism reference:
- telescoping steel arms with friction hold
- a 2-axis gimbal with independent springs
- flex cable wrapped through the joint
- a hidden pin-release for service
- magnetic, swappable cushions
Cables through the joints (hollow-shaft actuators, service loops inside the covers). Zero external cable ties.

14. Behavior: how Apple designs robot motion

From Apple ML Research's ELEGNT (lamp robot, 2025): motion is planned for function + expression across the whole trajectory. The path itself carries meaning.

Intention: show what's next. Orient toward the target before reaching.
Attention: look at the speaker; share gaze on objects.
Attitude: a pause reads as hesitation, decisive motion as confidence. Nod and shake.
Emotion: bouncy = happy, slow = calm, lowered = sad, jerky = fear.

Rules:

Rich expression for social and companion tasks; restrained for critical tasks, where extra motion reads as unsteady.
No unmotivated motion. Staring while motionless reads as "creepy."
Gestures must match real sensors. Implying a camera the robot doesn't have "felt fake."
Motor noise distracts.
Sync motion with voice and light.
Interruptible, cancelable, brief. Avoid motion in the user's periphery.

15. Thermals & headroom

Shell = heatsink. Internal fins and thermal pads to the shell; copper only where it's needed (the Studio Ultra is 2 lb heavier for its copper).
- Respect touch-temperature limits (IEC 62368-1 / ISO 13732-1). Bare metal held for long periods should stay ≈43–48 °C or below.
- Keep handles, lift points and human-contact skins out of the heat path.
Stack internals by heat. The Mac mini 2024 puts the PSU on top and the SoC and fan at the base.
Never let an iconic form freeze the architecture. The 2013 Mac Pro "designed ourselves into a bit of a thermal corner," and Apple apologized. If you copy the purity, copy the headroom: plan the next-generation power budget, connectors and modules.

16. Service, internals, marks

Service through one designed opening: lift the whole shell off (Mac Pro), slide the core out (G4 Cube), or a magnetic panel. Fasteners go on the underside, under feet or seals.
- Exterior screws, if any, are color-matched (Apple matches its pentalobes to the finish).
- Torx inside, a small fastener vocabulary, and shields ("cowlings") over every connector.
Durability first, then repair. Apple: "optimizing for repairability alone may not yield the best outcome."
- Field-serviceable modules are part of the design.
- "Screw attach over adhesives" (MacBook Neo).
- Debond-on-command or stretch-release adhesive on batteries.
The inside is designed too. "You'd know it's there" (Jobs). Orderly harnesses, symmetric heatsinks, cable-free modules, printed labels, black boards.
Marks:
- One logo, on the axis, on the back or top. Gloss on matte (polished deboss, an unetched spot on etched glass). No text on the front, no stickers, no badges.
- Consumer electronics: regulatory text, serials and QR codes go under a hatch, in a recess, or in the app (Apple uses e-labels; FCC e-labels need a built-in display).
- Machinery and robots: the EU Machinery Regulation and ISO 12100 require a visible, durable nameplate and CE mark. ISO 3864 / ANSI Z535 warning labels go at the hazard.
  - Treat these as designed elements: one laser-etched nameplate on a secondary face (base or rear), aligned to the grid, with no stickers.
  - Use etched or pad-printed warning marks in the system typeface.
- Third-party compatibility badges, including Apple's MFi badges, go on packaging only.
- Never put Apple's logo or trade dress on your product.
Environment:
- Recycled-content aluminum.
- Mono-material assemblies where possible; separable magnets.
- 100% fiber packaging with no plastic film, and paper pull tabs.
- No leather or PVC.
- A one-page environmental summary with real numbers.

17. Robot part → Apple move (quick map)

Robot part	Apple precedent	Move
Head / sensor array	iPhone 17 Pro / Air plateau, Face ID black glass	One plateau, 2 relief tiers, IR-transmissive dead-front, semi-gloss black lens trim, FOV cones modeled
Torso / base	Mac mini, Studio, iMac G4 dome	One primitive, inset base on a shadow gap, mass low, vents hidden underneath
Joint / actuator cover	Watch band slide-lock, AirPods Max gimbal	Concentric shroud, 0.3–0.5 mm rotating gap, hidden latch, one radius family
Arm / neck	iMac G4 neck, Pro Stand	Counterbalanced, thin, gleaming; holds within 2°
Gripper	AirPods Max cushions, Watch Sport Band	FKM/LSR pads, magnetically swappable, linkage pinch points covered
Mobile base / wheels	Mac Pro wheels	Jewelry-grade machined hubs, flush caps, integrated tread band
Handle / lift point	Mac Pro handles	Polished stainless that is the frame
Dock / charger	MagSafe, Watch puck, Figure 03 feet	Magnet ring + key magnet, center inductive or pogo, self-aligning, no false attach
Status	Hidden LED, HomePod top	One light, invisible until lit, white / amber / green
Primary control	Action button / Camera Control / Crown	One function, flush jewel cap or guarded knurled dial, haptic detents
E-stop	(ISO 13850)	Red mushroom proud, on a yellow ring flush in the shell, guard collar from the body form
Soft skin	HomePod mesh, Vision Pro knit, Figure 03 / 1X NEO	3–8 mm foam + 3D knit offset, seams underneath, hard-point attachments, no sharp substructure
Battery	iPhone 16 debond adhesive	Removable pack that forms part of the outer surface, keyed, hidden latch
Rugged / outdoor	Watch Ultra	Raised lips (≥ 0.85 mm) around glass, guards around controls, one accent, symmetric honest screws

Precedent details: references/products-desk-stationary.md, references/products-handheld-wearable.md.

18. What makes it NOT Apple (anti-patterns)

Tangent-arc corners on large reflective faces; fillet bulges; 3-fillet blobs; zebra kinks.
Mixed edge families; breaks of different sizes; a 0.1 mm "almost flush" step; uneven gaps.
Visible screws on A-surfaces; exposed cables or zip ties; stickers; text on the front.
Louvers, exposed heat-sink fins, mixed hole sizes, randomly truncated hole fields.
RGB / decorative lighting; rows of LEDs; screens on the body for branding.
More than two body colors; accent color spread over many parts; painted plastic faking metal.
Bolt-on bosses and brackets; a cosmetic shell over a visible frame; parts stacked like a kit.
Automotive high gloss on large areas (it shows every wave); chrome-and-LED sci-fi; a "robot face."
Apple's own failures to avoid:
- a sealed iconic form with no thermal headroom (Mac Pro 2013)
- a fragile mechanism traded for 1 mm (butterfly keyboard)
- a glossy surface replacing a proven physical control (Touch Bar)
- a port that disables the product (Magic Mouse)
- purity that pushes complexity into dongles (2016 MacBook Pro)

How Apple differs from Braun, Teenage Engineering, Nothing, Dyson, Muji, Figure, 1X and Optimus: → references/philosophy-and-process.md.

19. Presentation (renders)

Specimen style: the object isolated on seamless #F5F5F7 (or white), or near-black #000–#1D1D1F. Floating, or on a soft contact shadow. No props, no lifestyle scenes.
Camera: hero 3/4 at 20–30° elevation, plus a pure profile and a top-down. Long lens, 85–200 mm equivalent, verticals vertical.
Lighting:
- 3–5 large rectangular gradient softboxes: key ~2× the product size, a fill, and narrow rim strips behind to draw chamfers and silhouette.
- Black cards keep the dark edge definition on aluminum.
Detail shots: a macro of the hero chamfer carrying one continuous gradient highlight. Exploded views along one axis, evenly spaced, on dark with rim light only.
Material starting points:

Material Setting
Blasted aluminum Roughness 0.15–0.30, fine noise on roughness
Polished metal Roughness 0.05–0.10
Glass IOR 1.5
Black gloss Roughness 0.02–0.05

KeyShot and Blender settings: → references/cad-workflow.md §5.

20. Process

Name the manufacturing process for every visible part first ("CNC 6061, blast, Type II clear"), then let it set radii, draft and parting lines. A part with no plausible route to manufacture is not Apple.
Build the primitive and the plan outline with continuous corners in the sketch. Then fillet in order:
- hero rolls
- feature edges
- cosmetic breaks last
- Draft goes in before the fillets.
Make 3–5 parametric variants of the key proportion or radius, judge them at 1:1 in context, commit, and write down why.
Verify with analysis, not wireframes: zebra stripes across every hero transition, curvature combs on the main sections, draft analysis on textured faces, and a gradient-softbox render.
Design the touch points last and longest: feel, sound, force, and the first touch out of the box.

21. Robot safety & standards (aesthetics must fit inside these)

Contact with people (ISO 10218-1/-2:2025, ISO/TS 15066)

Transient and quasi-static contact force and pressure limits depend on the body region.
Larger radii and larger contact areas lower the pressure. This is where Apple-style generous rounds earn their keep. Avoid edges and corners under ~R5 on moving parts that can touch people. Prefer soft skins over the hard points.

Product-class standards

ISO 13482: personal-care robots.
ISO 3691-4: driverless and mobile platforms (warning lights and sounds, bumpers, speed zones).
UL 3300: service, communication, information, education and entertainment robots.

E-stop and controls

ISO 13850 color and form, plus ISO 13849 for the circuit (PL), so the styling can't compromise it.
Add an enabling device or teach-pendant mount, brake-release access, and manual-move handles where the robot must be pushed by hand.

Motion mechanics of the skin

Thin skins on moving links have stiffness and resonance; check for drumming and rattle at actuator frequencies.
Keep a shell mass versus payload and inertia budget.
Check impact and drop survival of cosmetic parts.
Check cable flex life through every joint (bend radius, cycles).

Environment and maintenance

Washdown or cleaning chemistry (food, medical).
UV and outdoor durability of the anodize, paint and elastomers.
Field-swappable wear parts (pads, tires, bumpers).
Recalibration access for sensors.
Fiducial and calibration targets, designed in as flush inlays.
Fleet ID marking, as one etched ID per unit, not stickers.

A metal unibody shell needs designed RF windows (glass, ceramic or unfilled plastic) for Wi-Fi, BLE, UWB, GNSS and cellular.
Avoid carbon-black or metallic paints and metallized coatings over antennas (ADG §4.9.1).

Review checklist (score each 0–2, mark N/A; ≥ 80% of applicable points reads as Apple)

Reduction: one primitive per module, one hero gesture, nothing unjustified?
Proportion: simple ratios, shared axes, symmetric, equal margins?
Corners: continuous curvature in plan view; no G1 snaps on A-surfaces?
Edges: one family, uniform break size, ≥ R0.3 under anodize?
Concentricity: every nested radius = parent − offset?
Seams: on material or direction changes, symmetric, constant width?
Gaps / flush: even, within budget, flush or deliberate, never "almost"?
Material: one structural material, honest, a process named for each part?
Color: one neutral body, at most one accent on one functional element, cables matched?
Openings: vents hidden, a texture, or structural; one hole size; ports grouped with lands?
Windows: FOV clear, chamfered semi-gloss black trim, ≥ 0.85 mm protective lip?
Controls: minimal, one function each, feel and sound specified, reachable?
Light: one status light, invisible until lit, no decorative LEDs?
Dock / charge / attach: self-aligning, keyed, product usable while docked, one matched cable?
Mechanisms / behavior: counterbalanced, holds position, cables internal; motion purposeful and expressive only where it helps?
Service / marks / safety: one designed service path, hidden fasteners, one logo, required marks designed in (not hidden), e-stop compliant, thermal headroom, touch temperature, pinch/shear gaps?

For each item that fails, give the exact fix and the number.

Quick reference

Need	Value
Plan corner	Continuous (one quintic Bézier per corner), visual R ≈ 20% short side (desk) / 25% (hand) / 8% (panel); extent E ≈ 1.41 R
Side section	40–60% true flat + G2 roll R ≈ 0.25–0.35 t
Machined edge break	0.3–0.6 mm uniform; ≥ R0.3 / C0.2 under anodize
Bright chamfer	0.3–0.6 mm × 45°, identical all round, cut after anodize (optional clear re-anodize)
Nested radius	R_inner = R_outer − offset
Gap	0.10–0.20 mm machined / 0.15–0.30 molded, ±0.05 (small parts); scale up with size, heat and load; reveals on long seams
Flush / step	±0.05 mm, or a deliberate ≥ 0.5 mm step / 0.3–0.6 mm reveal
Button	Proud 0.3–0.6 mm, gap 0.10–0.20, travel 0.2–0.4
Glass protection	≥ 0.85 mm (1.0 ideal) recessed below a lip
Proportions	1:3, 2:5, 1:2; square footprints
Finish	Glass or zirconia bead ~100–170 mesh + Type II anodize 10–15 µm, Ra 0.4–1.0 µm
Paint (prototype)	2K PU, satin 20–30 GU @ 60°; never high gloss on large areas
Molded draft	0.5–1° polished; ≥ 3° light texture; ≥ 5° medium
Color match	ΔE00 ≤ 1.0 between mating parts, D65 + LED
Hidden LED	Micro-perforations 20–80 µm through a wall thinned to 0.25–0.4 mm, or 5–15% smoked dead-front
Status palette	White system, amber attention/charging, green done
Dock	Magnet ring + key magnet, self-align ≤ 1.5 mm, no false attach
Mount / arm hold	Within 2° after 4 h and after vibration
Joint shroud gap	0.3–0.5 mm, concentric with the axis
Render	#F5F5F7 seamless, 85–200 mm lens, 20–30° hero, gradient softboxes

Reference files (load when needed)

references/form-geometry.md: corner tables measured from Apple drawings, edge sections, plateau steps, tolerances, perforation and port rules.
references/cmf-materials.md: aluminum, titanium, glass, polymers, fabrics; hidden-LED and logo methods; color table; small-team finishing recipes.
references/cad-workflow.md: SolidWorks/Fusion/Onshape/Rhino/OCC how-tos, verification, fillet order, DFM, hidden fasteners, rendering, robot-specific moves.
references/apple-official-docs.md: numbers from the Accessory Design Guidelines (MagSafe, buttons, ports, camera trim, bands), the HIG (haptics, crown, feedback, concentricity), environmental reports, and the ELEGNT robot-motion paper.
references/philosophy-and-process.md: Ive and Rams principles with sourced quotes, the ID studio process, leadership and language shifts to 2026, failures, a comparison with other design languages.
references/products-desk-stationary.md and references/products-handheld-wearable.md: product-by-product precedent catalogs with robot mappings.
scripts/apple_corner.py: continuous-corner outline generator and G1/G2 checker (standard library only).

Confidence: many numbers in this file are working values (practice/estimate), not Apple specs:

gaps and flushness
blast mesh and Ra
the Crown knurl pitch
the color hex values
the corner percentages

Say so when you quote them. Values tagged as estimates in the reference files are working numbers. Apple publishes no gap, gloss, color or Ra specifications. Treat the drawings and the ADG as authoritative, and everything else as informed practice.

HashBrake/apple-hardware-design

What is apple-hardware-design?

Ask in your favorite AI

Documentation