WHOI Pump

What it is

The WHOI Pump is a peristaltic pump for in-situ seawater sampling. The
pump head is a stock part; everything around it is original work: the
pressure housing, the controller, the firmware, and the deployment harness.

The current published version is v2. v1 is preserved as an earlier release
for anyone reproducing the original 2023 work.

Why we built it

Commercial in-situ pumps are expensive and rarely repairable in the field.
The original v1 prototype was the cheapest thing we could build that
didn't compromise on flow rate or duty cycle. v2 fixes the v1 seal-stack
leak and cuts standby power.

How to use it (v2)

Charge the battery (8.4 V LiFePO4, internal pack).
Set the duty cycle and total run time over USB before deployment.
Confirm the dry test passes (motor draws < 350 mA at 200 mL/min).
Deploy.

See firmware/README.md in the upstream repository for the full
configuration protocol. The v2 firmware is not backwards-compatible with
v1 hardware.

Known issues

The status LED ring on v2 is bright enough to wash out at the surface in
daylight; consider a sun shroud.
v1 hardware still in the field has the seal-stack leak above 200 m. The
v2 redesign solves it but requires a head-and-housing swap.

Contributors

Alice Researcher — Project lead

Bob Engineer — Hardware design

Carol Lab Lead — Principal investigator

Ran the lab effort and supported the field deployment.

Cite this project

Project DOI (always points at the latest version): 10.5281/zenodo.99000

Cite as

Alice Researcher, Bob Engineer, & Carol Lab Lead (2026). WHOI Pump (Version v2). OSPREY · Zenodo. https://doi.org/10.5281/zenodo.99002

Cite the project DOI for the work as a whole. Cite a version DOI when you need to point at exactly one snapshot.

Submitter's self-rating

8/10 (self-reported by the submitter)

Two release generations field-deployed off the R/V Tioga and on Vineyard Sound moorings. v2 seal stack and external LED resolved the main v1 pain points; power draw cut by ~30%. Still wants more bench time on the new MCU firmware before I'd call it solid above 600 m.

Citations (4)

Pfeifer, A. (2024). Revised seal stack performance in the WHOI Pump v2. WHOI tech report 2024-03. (2024)

Hall, B. (2023). Vineyard Sound mooring write-up referencing pump v1 deployment. (2023)

Hall, B. (2023). Field notes from a six-week mooring deployment. Internal WHOI report. (2023)

Pfeifer, A. et al. (2023). A low-cost in-situ pump for coastal sampling. Ocean Engineering Letters. (2023)