---
title: "Raymond Goertz's 1949 Argonne report (ANL-4311) documents \"the first completely master-slave manipulator known to exist,\" and never once uses the word \"waldo\""
type: "claim"
status: "seedling"
writer_model: "claude-sonnet-5"
audit_status: "capture-verified — the full 8-page report was fetched directly via extract_pdf from OSTI at capture time (2026-09-04) and read in full; source_sha carried forward from the capture; no independent re-fetch this promotion (headless, per the standing no-network-in-promotion design). | AUDIT 2026-09-05 (scheduled cross-model audit, claude-opus-5; writer claude-sonnet-5): ANL-4311 independently re-fetched from OSTI via extract_pdf — sha256 951f9e87…3861263 identical to the recorded source_sha, TLS verified, 8 pages, and the full text read. No defect found. Confirmed verbatim: the tongs/shielding-barrier opening, 'It is called a Master-Slave Manipulator because the slave tongs move in exact correspondence with a master handle', and 'This is the first completely master-slave manipulator known to exist and has proved that this type of manipulation is very successful when the unit is properly engineered and built.' Also confirmed: date 7 March 1949; declassification 'Classification Cancelled by Authority of the Declassification Officer, USAEC, June 24, 1949'; Remote Control Engineering Division under H. L. Hull; contract W-31-109-eng-38; 'seven completely independent mechanical connections or linkages' decomposing as three lineal, three rotational and one jaw motion; the ~3-foot master-slave displacement; and 'behind a barrier such as a lead glass window'. Both absence claims hold: 'waldo' occurs nowhere in the document, and 'radioactive' occurs nowhere. Worth recording for a future auditor — the words 'Radiological' and 'Radiation' do appear, but only as institution names in the front-matter distribution list (Naval Radiological Defense Laboratory; University of California Radiation Laboratory), never in the report body, so the note's careful phrasing 'the report's body never uses the word radioactive' is exactly right and should not be loosened. Caveat: OSTI's scan extracts by OCR, so an absence claim rests on OCR fidelity; the text is clean and legible throughout, but a hand-check of the page images would be the stronger receipt."
source_url: "https://www.osti.gov/servlets/purl/1054625"
source_sha: "951f9e87f091a4fb86d738d222c1ba68e756370885b53d133d5f4d9d53861263"
source_title: "Master-Slave Manipulator"
source_author: "R. C. Goertz, Remote Control Engineering Division (H. L. Hull, Director), Argonne National Laboratory"
source_date: "1949-03-07T00:00:00.000Z"
source_venue: "Argonne National Laboratory, report ANL-4311 (operated by the University of Chicago under AEC contract W-31-109-eng-38); archived by the U.S. Department of Energy Office of Scientific and Technical Information (OSTI)"
source_tier: 1
source_quote: "A device for manipulating a pair of tongs behind a shielding barrier has been built and tested. It is called a Master-Slave Manipulator because the slave tongs move in exact correspondence with a master handle. [...] This is the first completely master-slave manipulator known to exist and has proved that this type of manipulation is very successful when the unit is properly engineered and built."
provenance: "Promotion from 10-inbox/raw/2026-09-04-verify-the-waldo-teleoperator-lineage-goertzs-argonne-masterslave.md, 2026-09-04 (headless)"
origin: "batch"
derived_from: ["20260904-0223-verify-the-waldo-teleoperator"]
date_created: "2026-09-04T00:00:00.000Z"
verifies: "question-verify-waldo-teleoperator-lineage-goertz-character-shop"
tags: ["nuclear-engineering","teleoperation","invention-history","verification","etymology","hop"]
seek_code_commit: "290e6f6"
---


**verifies**: [[question-verify-waldo-teleoperator-lineage-goertz-character-shop]]

Raymond C. Goertz's technical report ANL-4311, "Master-Slave Manipulator" (Remote Control Engineering Division, Argonne National Laboratory, dated March 7, 1949, declassified by the AEC on June 24, 1949), describes "a device for manipulating a pair of tongs behind a shielding barrier," built and tested, "called a Master-Slave Manipulator because the slave tongs move in exact correspondence with a master handle." The report closes: "This is the first completely master-slave manipulator known to exist and has proved that this type of manipulation is very successful when the unit is properly engineered and built." The device used seven independent mechanical linkages (three lineal, three rotational, one squeeze-to-close) between a master handle and slave tongs displaced roughly three feet away, operable "behind a barrier such as a lead glass window." The report's body never uses the word "radioactive"; the AEC contract number, the declassification stamp, and the shielding-barrier language support but do not verbatim-state a radiological-handling purpose — worth flagging rather than silently upgrading.

A full read of the document turns up no instance of the word "waldo" anywhere — the device and its parts are named "Master-Slave Manipulator," "master handle," and "slave tongs" throughout. This is a direct-primary confirmation that the nickname now generically attached to remote manipulators, per the Wikipedia-sourced etymology in [[claim-waldo-coinage-heinlein-1942-to-nuclear-teleoperators]] ("the real-life remote manipulators that were later developed also came to be called waldos, some even by NASA"), was applied to Goertz's device from outside, sometime after 1949, rather than by Goertz himself.

This report is the earliest Tier-1-documented instance of the device class the word "waldo" later attached to, and upgrades to Tier 1 the previously cyberneticzoo.com-sourced Goertz/Argonne detail in [[claim-waldo-coinage-heinlein-1942-to-nuclear-teleoperators]].

> [!note] Seek's commentary:
> The nicest detail in a government report is usually the thing it doesn't claim. Goertz calls his own machine "very successful" and stops there — no radioactive material named outright, no "waldo" anywhere in eight pages. The caution reads as more credible than a flashier report would have, and it's the same caution that makes the absence of "waldo" a real finding rather than a null result: a word has to come from somewhere else if the man who built the thing never used it. — Seek