Reference chip · BYU combined pump + mixer

Watch it print.

A 3D printer builds this chip by hardening one thin slice of liquid plastic at a time. This one takes 1,150 slices, each a hundredth of a millimetre thick. Scroll to watch it build. These are not drawings — each picture is a real slice through the design.

↓ SCROLL TO BUILD

A computer render of the BYU combined pump and mixer chip part-way through a print: a translucent resin block with the amber internal channel and chamber network sealed inside it, and the cyan cross-section being cured across the top.

LAYER 0 / 1,150 · z = 0.00 mm

01 — TEN MICRONS AT A TIME

The block accumulates

The printer cures one full cross-section of resin, drops ten microns, and cures the next. Nothing is carved and nothing is joined — the part grows upward out of the vat. Cyan is the cross-section being written at this instant.

02 — THE NETWORK, THROUGH THE RESIN

What is already sealed inside

Cured resin is translucent, so the block is drawn see-through here and the finished interior shows through it. Amber marks void — channels and chambers already roofed over below the build plane. Nothing was drilled and nothing was bonded: the printer simply never cured resin there. That liquid resin still has to be cleared out after printing, and the lab reports prints where it could not be (Hardware and process, section 6).

03 — NINE ACTUATED CHAMBERS

The pump and the mixer

The widest cross-sections belong to the nine pneumatically actuated chambers that give the chip its name. Each carries a pressure line and a purge line — eighteen pneumatic ports in all.

04 — 1,150 LAYERS LATER

One part, no assembly

Roof closed, only the ports still open. Pump, mixer, nine chambers and all twenty-six routed nets — designed to leave the printer as a single monolithic block, 19.46 × 12.05 × 11.50 mm, with no bonding step.

The build, by the numbers

1,150

layers at 10 µm

11.50 mm

build height

internal void bodies

DRC violations

Placed by software, not drawn by hand. The channels, valves and chambers were laid out by the OpenMFDA design flow from a specification, the way electronic chips are laid out from a circuit description.

An H.R.3.3 design, checked in CAD. We have checked the design on a computer: it is sealed, every channel joins up where it should, and nothing overlaps that should not. Everything on this page describes the drawing.

Technical details

A CAD design for experimental printing. The geometry is watertight, DRC-clean and topologically checked in CAD.

Geometry credit: Nordin Group, BYU, with the State of Utah Center of Excellence for Biomedical Microfluidics, University of Utah. The design shown on this page is the Nordin Group's, BYU, and its images here are not under this site's MIT licence; for their terms, ask the Nordin Group. · Back to the library