Shapeshifting Pegasus Drone Both Drives And Flies, Now Has Smart Radio
Robotic Research, developer of self-driving truck kits for the Army, and Persistent Systems, a manufacturer of high-tech smart radios, announced early in January that they are deepening their collaboration with an agreement to fully integrate the former company’s devices into the latter’s smart radio ecosystem.
That agreement is particularly aimed at enhancing Robotic Research’s Pegasus family of drones, which like Starscream from Transformers, can change shape between ground and aircraft modes.
All three Pegasus variants can roll quietly on the ground on narrow side-mounted tracks with high ground clearance. In that mode it may use its four rotors to perform short hops over obstacles such as train tracks that are insurmountable to many unmanned ground vehicles (UGV)
But when a Pegasus switches to sustained flight mode, its tracks flip upwards, shifting the center of gravity to improve aerodynamic stability. That opens up a 360-degree field of view for its cameras, and shields the rotors from collision damage, particularly while indoors—yes, all three models can fit through a typical doorway or window.
The tiny football-sized Pegasus Mini model can be stuffed into a backpack and is designed primarily for surveillance/reconnaissance roles in tight spaces using a fixed electrooptical/ infrared camera.
The medium-sized Pegasus IIe (15 pounds total including batteries) has twice the maximum payload at four pounds and can also carry CBRNE hazard sensors which detect chemical, radiations, explosives etc.
Finally, the 38-pound Pegasus III can carry between 10 and 20 pound payloads, including a more flexible gimbaled camera. Other equipment options include systems to detect and dispose of explosives, LIDAR sensors used to create three-dimensional terrain maps, and potentially even electronic warfare jammers and sensors.
The Pegasus drones have up to 30 minutes of flight endurance, but can drive much longer on the same battery, ranging from 2 hours for the mini to 8 hours for the Pegasus III.
All types are operated via a ruggedized videogame-style PUCK controller which uses ATAK software developed by the Air Force Research Laboratory mated to a commercial Android UI. The operator can use the controller to issue task commands to multiple drones without having to exert direct control.
Cursory research revealed only limited prior commercial development of UAS/UGV hybrids despite some academic studies of the concept. But beyond the cool factor, what’s the point of developing a hybrid air/ground drone? The Pentagon, after all, has yet to explicitly request such a platform.
Alberto Lacaze, co-founder and president of Robotic Research, and Jeffrey Washington, director of business development at Persistent, were happy to explain their thinking in a teleconference this January.
“[Pegasus] is challenging because it doesn’t fit the government’s traditional UAV or UGV development pathways,” Lacaze admitted. “But we think it will change minds, and sooner or later we will have requirements for machines that have hybrid capability.”
For starters, there’s the logistical advantage of having a single hybrid drone that can do the jobs of both air- and ground-based unmanned systems. Furthermore, hybrid UAS/UGVs may be particularly useful for accessing hard-to-reach places like building interiors.
Though not intended for long-distance ops (their maximum range can be measured in “miles” according to Lacaze), in some scenarios the Pegasus’s hybrid nature may give it an endurance edge because it doesn’t have to remain continuously in flight. For example, a Pegasus could land on the roof of a building, and “perch and stare” using its cameras to surveil the surrounding area for days without consuming much battery.
If it eventually becomes necessary to scout inside a nearby building, they could enter through a door on the roof or hover through a window, and then quietly search the inside rolling on treads.
Communications, Navigation and AI Innovation
An unmanned system’s command link is both a lifeline and Achille’s heel, vulnerable to disruption by everything from dense terrain (hills, buildings, concrete walls) to inclement weather and hostile jamming. Terrain especially limits remote-control range for ground vehicles.
To mitigate these problems, Robotic Research integrated redundant control, communication and navigation systems into the Pegasus series, beginning with their ability to execute missions autonomously, with surveillance data recorded internally, should their command link be disrupted.
Furthermore, the drones use inertial navigation systems (INS) based on the WarLoc “boot-box” system designed by Robotic Research to help track dismounted personnel even in a GPS-denied environment. Unlike traditional INS systems, each WarLoc uses a radio to form a distributed network with other nearby WarLoc devices to keep more precise tabs on their relative positions.
Robotic furthermore sought to ensure a robust radio link by integrating Embedded Modules developed by Persistent Systems into its Pegasus II and III drones. The modules, roughly the size of a pack of playing cards, are a miniaturized derivative of Persistent’s MPU5 smart radio, which runs the company’s Wave Relay mobile ad-hoc network (MANET).
According to Washington, the module’s node-hopping capabilities combine “scalability with mobility”, allowing numerous devices to rapidly and automatically mesh together on the same frequency. While the MPU5 can theoretically maintain ground-air links at ranges of up to 130 miles, on Pegasus the biggest benefit is throughput and latency.
“There are many radios that can do meshing, but few that don’t increase latency significantly when doing hops,” Lacaze concurred. “If you have to do 2-3 hops of the radios, you wind up with a second or two of delay. That’s a non-starter when trying to tele-operate a vehicle. Having something with meshing and penetration, as wells as doing all of that with low-bandwidth and good latency is a must.”
Washington says Robotic Research was the first company he visited while working with Persistent. “I was like ‘man this is cool!’ From that point I felt we needed to have these guys be part of our LTA program where we say ‘we can give you more engineering time.’ We’re very excited to have them as part of our ecosystem.”
In addition to enhancing the distributed navigation capabilities of WarLoc, the mesh network relays signals. That could enable an operator to maintain a link to distant ground drone by using nearby airborne drone as an intermediary, a potentially useful trick for communicating with a drone in a low wireless-penetration environment like a culvert, cave or building.
The distributed radio network is also key to implementing “swarming” AI behavior, in which multiple drones cooperate to perform complex tasks based on a simple command.
“Through the ATAK software system, you assign an area and the drones automatically assume trajectories to perform a mission without having to set waypoints for each drone,” Lacaze explained. “Because if you have 10 vehicles, creating all those waypoints in a timely manner becomes impossible. And they’ll share and update their behavior based on what they find.” Pegasus’s autonomous mapping capability was successfully tested by the U.S. Army in 2020.
“Now say we want to survey a Landing Zone. It may have a lot of terrain or buildings, so you might fly some birds to create a 3D map of the LZ to make sure there are no obstructions. Or you could have a large group coordinate to find the source of a chemical emission, or scan an indoor space.”
Robotic Research also is pursuing a concept for Manned-Unmanned Teaming (MUM-T) through a kit using a power/communication cable to tether a Pegasus to a vehicle for rapid field deployment. Though using a tether for an air/ground platform seems tricky, Lacaze described a concept of operations:
“Say you have convoy going somewhere. If it encounters [a possible threat], normally it stops and becomes very vulnerable. So having a bird that can takeoff from one of those vehicles and provide long-endurance oversight over the area is very important.”
Of course, any network that gives commanders more precise information and control over unmanned systems could theoretically be disabled, or worse, exploited by hostile forces. However, Lacaze insists that Pegasus remains relatively secure because its links are designed for jamming resistance and Low-Probability-of-Detect and Intercept (ie. radio wave stealth).
Next: Battlefield Delivery?
Eventually, Lacaze envisions developing a larger Pegasus IV hybrid UAV/UGV that could potentially fulfill the U.S. Army’s JTAARS requirement for a drone that can haul up to 800 pounds of supplies to help sustain ground formations in the field, as well as a Navy requirement for a 50-300 lb load-hefting delivery drone. The Marine Corps meanwhile is testing medical delivery drones.
Lacaze points out that aircraft that can lift large payloads intrinsically require larger landing zones, which could pose problems for resupplying frontline troops. “It’s very difficult to land [a large drone]. The advantage that we have with Pegasus is we can land at a different location than where want to deliver to.”
The Pegasus II model began low-rate initial production in 2020, with several being operationally tested by the U.S. Army. Time will tell whether the Pegasus can find a permanent entry into the Pentagon’s diverse unmanned system programs.
Lacaze maintains that Pegasus has generated interest despite having only been made public a year ago: “We’ve been driven to push the envelope by the Special Forces community. But we’ve found there are other users interested in the capability even on the commercial side.” He later wrote me these include clients with “…interest in using Pegasus for inspection of culverts, power plants, and power distribution.”
Read the article on Forbes.