Our take
Square Robot owns a narrow but valuable niche: on-stream internal inspection of fuel and chemical storage tanks. Its SR-3 robot dives into a tank that is still in service, so owners skip draining, cleaning, degassing, and confined space entry.1,2
The evidence is solid for a small company: more than 400 tanks inspected, FM approvals for hazardous locations, and Marathon Petroleum as both investor and user. Weak points are a small balance sheet, with $13.5 million raised in its Series B, and no published prices.2,3,4,5
Scores by criterion
Each criterion is defined on our methodology page.
Who uses Square Robot and what it's for
Owners of aboveground storage tanks in refining, petrochemicals, aviation fuel, terminals, and power generation use Square Robot for API 653 and EEMUA 159 internal inspections.1
Marathon Petroleum deploys the company's fleet across its terminals and refineries.4
History
Square Robot was founded in Massachusetts in 2016, built its first prototype in 2017, and inspected its first tank in 2019. It reached 100 tanks in 2023 and passed 400 in 2026.2
It closed a Series B in November 2024 and added $7.5 million in December 2025 with Marathon Petroleum, bringing the round to $13.5 million. In September 2026 it won the NIOSH Prevention through Design Award.3,5,4,6
SR-3 and Side Launcher
The SR-3 is a submersible robot that inspects tank floors with a phased array ultrasonic probe. The company says its patented navigation places corrosion readings within a six inch radius, and that its defect detection reached 99.6% confidence against API 653 Annex G sizing expectations.1
The SR-3 and its Side Launcher deployment system carry FM approvals for Class I Division 1 and Division 2 hazardous locations.3
Pricing
Square Robot sells inspections as a service and does not publish prices. It offers an online value calculator that estimates savings in confined space labor hours, inspection days, and total cost.1
Competitive landscape
| Company | Product | Pricing model | Deployment footprint | Where Square Robot wins or loses |
|---|---|---|---|---|
| Square Robot | SR-3 submersible robot for internal tank inspection1 | Inspection service; prices not published1 | More than 400 tanks inspected; Marathon Petroleum is a user and investor2,4 | In-service internal tank inspection; prices not published |
| Gecko Robotics | Inspection robots and sensors plus Cantilever software9 | Not published9 | US Navy contract vehicle expanded to $300 million9 | Gecko wins on crawler inspection of boilers, pipes, and tank walls. Square Robot wins on tank floors while the tank stays full. |
| Flyability | Elios 3 collision-tolerant drone for indoor and confined-space inspection11 | Not published; sold through distributors in 27 countries10 | Customers across 68 countries10 | Flyability wins on drone inspection of empty confined spaces. Square Robot wins on tanks that stay in service. |
| ANYbotics | ANYmal and ANYmal X legged inspection robots14 | Quote only; about $670,000 per unit, derived from a $4 million order for six units16 | Close to 200 robots in the field by December 202413 | ANYbotics wins on routine walking patrols of plants. Square Robot wins on internal tank floor inspection. |
| Percepto | Autonomous drones and the AXION platform for site inspection15 | Not published15 | Utilities, solar, mining, oil and gas, and ports15 | Percepto wins on autonomous drone monitoring of whole sites. Square Robot wins on compliant internal tank inspections. |
Limits
Prices are not published.1
Revenue is not disclosed. We estimate it at $5 million to $15 million, based on roughly 100 tank inspections a year from 2023 to 2026. This is an estimate, not a reported figure.2
Total disclosed funding is modest, with a Series B of $13.5 million.5
What customers say
Where it helps
Across 385 tanks inspected, the NSC says Square Robot helped contain more than 695 tons of volatile organic compound emissions and reduced confined space entries to zero.8
Because tanks stay online, owners avoid the costs of removing product, cleaning, waste disposal, and degassing. The company says customers save hundreds of thousands to millions of dollars per tank.1,2
Where it falls short
Plants that need to inspect boilers, pipes, or tank walls rather than tank floors may get more from crawler or drone inspection vendors such as Gecko Robotics or Flyability.
Leadership
David Lamont
CEOLamont joined Square Robot in 2020 after more than 40 years in energy technology, including CEO roles at Proserv and ROVOP.7
Sources
- Square Robot, Homepage, accessed November 3, 2026
- Square Robot, About us, accessed November 3, 2026
- Square Robot, News, accessed November 3, 2026
- Square Robot, Square Robot announces new funding and collaboration, December 15, 2025, accessed November 3, 2026
- Worcester Business Journal, Westborough robotics firm raises $7.5M, capping off 2025 expansion efforts, accessed November 3, 2026
- Square Robot, Square Robot wins 2026 NIOSH Prevention through Design Award, September 16, 2026, accessed November 3, 2026
- EEMUA, Inspection Seminar 2025, Session 1 speaker profile, accessed November 3, 2026
- National Safety Council, NIOSH announces 2026 Prevention through Design Award, September 15, 2026, accessed November 3, 2026
- Gecko Robotics, Home page, accessed November 1, 2026
- Flyability, Home page, accessed November 1, 2026
- Flyability, Elios 3, accessed November 1, 2026
- Climate Investment, CI joins investment in ANYbotics, accessed November 1, 2026
- TechCrunch, ANYbotics raises $60M, December 12, 2024, accessed November 1, 2026
- ANYbotics, ANYmal X launch, accessed October 31, 2026
- Percepto, Home page, accessed November 1, 2026
- ANYbotics, Petrobras and ANYbotics Join Efforts to Automate Offshore FPSO Inspections, November 22, 2023, accessed October 31, 2026
