https://spectrum.ieee.org/darpa-robot [ ] IEEE.orgIEEE Xplore Digital LibraryIEEE StandardsMore Sites Sign InJoin IEEE The March issue of IEEE Spectrum is here! Download PDF | Close bar Just How Many Robots Can One Person Control at Once? Share FOR THE TECHNOLOGY INSIDER Search: [ ] Explore by topic AerospaceAIBiomedicalClimate TechComputingConsumer ElectronicsEnergy History of TechnologyRoboticsSemiconductorsTelecommunications Transportation IEEE Spectrum FOR THE TECHNOLOGY INSIDER Topics AerospaceAIBiomedicalClimate TechComputingConsumer ElectronicsEnergy History of TechnologyRoboticsSemiconductorsTelecommunications Transportation Sections FeaturesNewsOpinionCareersDIYEngineering Resources More NewslettersSpecial ReportsCollectionsExplainersTop Programming LanguagesRobots Guide /IEEE Job Site / For IEEE Members Current IssueMagazine ArchiveThe InstituteThe Institute Archive For IEEE Members Current IssueMagazine ArchiveThe InstituteThe Institute Archive IEEE Spectrum About UsContact UsReprints & Permissions /Advertising / Follow IEEE Spectrum Support IEEE Spectrum IEEE Spectrum is the flagship publication of the IEEE -- the world's largest professional organization devoted to engineering and applied sciences. Our articles, podcasts, and infographics inform our readers about developments in technology, engineering, and science. Join IEEE Subscribe About IEEEContact & SupportAccessibilityNondiscrimination PolicyTerms IEEE Privacy PolicyCookie PreferencesAd Privacy Options (c) Copyright 2025 IEEE -- All rights reserved. A public charity, IEEE is the world's largest technical professional organization dedicated to advancing technology for the benefit of humanity. Enjoy more free content and benefits by creating an account Saving articles to read later requires an IEEE Spectrum account The Institute content is only available for members Downloading full PDF issues is exclusive for IEEE Members Downloading this e-book is exclusive for IEEE Members Access to Spectrum 's Digital Edition is exclusive for IEEE Members Following topics is a feature exclusive for IEEE Members Adding your response to an article requires an IEEE Spectrum account Create an account to access more content and features on IEEE Spectrum , including the ability to save articles to read later, download Spectrum Collections, and participate in conversations with readers and editors. For more exclusive content and features, consider Joining IEEE . Join the world's largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum's articles, archives, PDF downloads, and other benefits. Learn more about IEEE - Join the world's largest professional organization devoted to engineering and applied sciences and get access to this e-book plus all of IEEE Spectrum's articles, archives, PDF downloads, and other benefits. Learn more about IEEE - CREATE AN ACCOUNTSIGN IN JOIN IEEESIGN IN Close Access Thousands of Articles -- Completely Free Create an account and get exclusive content and features: Save articles, download collections, and talk to tech insiders -- all free! For full access and benefits, join IEEE as a paying member. CREATE AN ACCOUNTSIGN IN RoboticsNewsJournal Watch Just How Many Robots Can One Person Control at Once? A DARPA project overturns longstanding assumptions Michelle Hampson 26 Jan 2025 4 min read Illustration showing a silhouetted swarm of drones with red eyes. Planet Flem/iStock This article is part of our exclusive IEEE Journal Watch series in partnership with IEEE Xplore. Swarms of autonomous robots are increasingly being tested and deployed in complex missions, yet a certain level of human oversight during these missions is still required. Which means a major question remains: How many robots--and how complex a mission--can a single human manage before becoming overwhelmed? In a study funded by the U.S. Defense Advanced Research Projects Agency (DARPA), experts show that humans can single-handedly and effectively manage a heterogenous swarm of more than 100 autonomous ground and aerial vehicles, while feeling overwhelmed only for brief periods of time during an overall small portion of the mission. For instance, in a particularly challenging, multiday experiment in an urban setting, human controllers were overloaded with the workload only 3 percent of the time. The results were published 19 November in IEEE Transactions on Field Robotics. Julie A. Adams, the associate director of research at Oregon State University's Collaborative Robotics and Intelligent Systems Institute, has been studying human interactions with robots and other complex systems, such as aircraft cockpits and nuclear power-plant control rooms, for 35 years. She notes that robot swarms can be used to support missions where work may be particularly dangerous and hazardous for humans, such as monitoring wildfires. "Swarms can be used to provide persistent coverage of an area, such as monitoring for new fires or looters in the recently burned areas of Los Angeles," Adams says. "The information can be used to direct limited assets, such as firefighting units or water tankers to new fires and hotspots, or to locations at which fires were thought to have been extinguished." These kinds of missions can involve a mix of many different kinds of uncrewed ground vehicles (such as the Aion Robotics R1 wheeled robot) and aerial autonomous vehicles (like the Modal AI VOXL M500 quadcopter), and a human controller may need to reassign individual robots to different tasks as the mission unfolds. Notably, some theories over the past few decades--and even Adams's early thesis work--suggest that a single human has limited capacity to deploy very large numbers of robots. "These historical theories and the associated empirical results showed that as the number of ground robots increased, so did the human's workload, which often resulted in reduced overall performance," says Adams, noting that, although earlier research focused on unmanned ground vehicles (UGVs), which must deal with curbs and other physical barriers, unmanned aerial vehicles (UAVs) often encounter fewer physical barriers. Aerial visualization of several drone swarms executing a mission. Human controllers managed their swarms of autonomous vehicles with a virtual display. The fuschia ring represents the area the person could see within the head-mounted display.DARPA As part of DARPA's OFFensive Swarm-Enabled Tactics (OFFSET) program, Adams and her colleagues sought to explore whether these theories applied to very complex missions involving a mix of uncrewed ground and air vehicles. In November 2021, at Fort Campbell in Kentucky, two human controllers took turns engaging in a series of missions over the course of three weeks with the objective of neutralizing an adversarial target. Both human controllers had significant experience controlling swarms, and participated in alternating shifts that ranged from 1.5 to 3 hours per day. Testing How Big of a Swarm Humans Can Manage During the tests, the human controllers were positioned in a designated area on the edge of the testing site, and used a virtual reconstruction of the environment to keep tabs on where vehicles were and what tasks they were assigned to. The largest mission shift involved 110 drones, 30 ground vehicles, and up to 50 virtual vehicles representing additional real-world vehicles. The robots had to navigate through the physical urban environment, as well as a series of virtual hazards represented using AprilTags--simplified QR codes that could represent imaginary hazards--that were scattered throughout the mission site. 3DR Solo, Uvify IFO-S, AION R1 with TX2 and Modal AI VOXL m500 UGVs and UAVs.Clockwise from top left: a 3DR Solo, Uvify IFO-S, AION R1 with TX2, and Modal AI VOXL m500 UGVs and UAVs.Phillip Walker et al. DARPA made the final field exercise exceptionally challenging by providing thousands of hazards and pieces of information to inform the search. "The complexity of the hazards was significant," Adams says, noting that some hazards required multiple robots to interact with them simultaneously, and some hazards moved around the environment. Throughout each mission shift, the human controller's physiological responses to the tasks at hand were monitored. For example, sensors collected data on their heart-rate variability, posture, and even their speech rate. The data were input into an established algorithm that estimates workload levels and was used to determine when the controller was reaching a workload level that exceeded a normal range, called an "overload state." Adams notes that, despite the complexity and large volume of robots to manage in this field exercise, the number and duration of overload state instances were relatively short--a handful of minutes during a mission shift. "The total percentage of estimated overload states was 3 percent of all workload estimates across all shifts for which we collected data," she says. www.youtube.com The most common reason for a human commander to reach an overload state is when they had to generate multiple new tactics or inspect which vehicles in the launch zone were available for deployment. Adams notes that these finding suggest that--counter to past theories--the number of robots may be less influential on human swarm-control performance than previously thought. Her team is exploring the other factors that may affect swarm-control missions, such as other human limitations, system designs, and UAS designs, the results of which will potentially inform U.S. Federal Aviation Administration drone regulations, she says. This story was updated on 27 January 2025 to clarify that the experiment studied only whether controllers were overwhelmed by the workload, and not whether they were stressed. From Your Site Articles * Kilobots Are Cheap Enough to Swarm in the Thousands > * Designing Customizable Self-Folding Swarm Robots > * Metal Spheres Swarm Together to Create Freeform Modular Robots > Related Articles Around the Web * DARPA: Home > autonomous robotsdisaster robotshuman robot interactionmilitary robotsdarpajournal watch Michelle Hampson Michelle Hampson is a freelance writer based in Halifax. She frequently contributes to Spectrum's Journal Watch coverage, which highlights newsworthy studies published in IEEE journals. The Conversation (1) David Deffry David Deffry27 Jan, 2025 INDV could've just asked a Starcraft player. 0 Replies Hide replies Show More Replies A black and white image of a woman surrounded by mathematical equations. ComputingOpinion The Coming Quantum Boom: A New Industry a Century in the Making 2h 2 min read A concept image showing a small robot consisting of a single leg and a large foot with two wheels on the sides performing a series of leaps across an icy landscape with water geysers. RoboticsNews Tiny Jumper for Enceladus Mission 5h 4 min read A woman in a jogging position, with one foot on the ground and the other lifted, while wearing a robotic brace around her stomach, feet and the sides of her legs. BiomedicalSensorsNewsHumanoid Robots A Self-Balancing Exoskeleton Strides Toward Market 02 Mar 2025 4 min read Related Stories RoboticsNewsHumanoid Robots Video Friday: Helix RoboticsNews Dual-Arm HyQReal Puts Powerful Telepresence Anywhere RoboticsNews Video Friday: Unitree Talent Awakening