Tag Archives: own
#437610 How Intel’s OpenBot Wants to Make ...
You could make a pretty persuasive argument that the smartphone represents the single fastest area of technological progress we’re going to experience for the foreseeable future. Every six months or so, there’s something with better sensors, more computing power, and faster connectivity. Many different areas of robotics are benefiting from this on a component level, but over at Intel Labs, they’re taking a more direct approach with a project called OpenBot that turns US $50 worth of hardware and your phone into a mobile robot that can support “advanced robotics workloads such as person following and real-time autonomous navigation in unstructured environments.”
This work aims to address two key challenges in robotics: accessibility and scalability. Smartphones are ubiquitous and are becoming more powerful by the year. We have developed a combination of hardware and software that turns smartphones into robots. The resulting robots are inexpensive but capable. Our experiments have shown that a $50 robot body powered by a smartphone is capable of person following and real-time autonomous navigation. We hope that the presented work will open new opportunities for education and large-scale learning via thousands of low-cost robots deployed around the world.
Smartphones point to many possibilities for robotics that we have not yet exploited. For example, smartphones also provide a microphone, speaker, and screen, which are not commonly found on existing navigation robots. These may enable research and applications at the confluence of human-robot interaction and natural language processing. We also expect the basic ideas presented in this work to extend to other forms of robot embodiment, such as manipulators, aerial vehicles, and watercraft.
One of the interesting things about this idea is how not-new it is. The highest profile phone robot was likely the $150 Romo, from Romotive, which raised a not-insignificant amount of money on Kickstarter in 2012 and 2013 for a little mobile chassis that accepted one of three different iPhone models and could be controlled via another device or operated somewhat autonomously. It featured “computer vision, autonomous navigation, and facial recognition” capabilities, but was really designed to be a toy. Lack of compatibility hampered Romo a bit, and there wasn’t a lot that it could actually do once the novelty wore off.
As impressive as smartphone hardware was in a robotics context (even back in 2013), we’re obviously way, way beyond that now, and OpenBot figures that smartphones now have enough clout and connectivity that turning them into mobile robots is a good idea. You know, again. We asked Intel Labs’ Matthias Muller why now was the right time to launch OpenBot, and he mentioned things like the existence of a large maker community with broad access to 3D printing as well as open source software that makes broader development easier.
And of course, there’s the smartphone hardware: “Smartphones have become extremely powerful and feature dedicated AI processors in addition to CPUs and GPUs,” says Mueller. “Almost everyone owns a very capable smartphone now. There has been a big boost in sensor performance, especially in cameras, and a lot of the recent developments for VR applications are well aligned with robotic requirements for state estimation.” OpenBot has been tested with 10 recent Android phones, and since camera placement tends to be similar and USB-C is becoming the charging and communications standard, compatibility is less of an issue nowadays.
Image: OpenBot
Intel researchers created this table comparing OpenBot to other wheeled robot platforms, including Amazon’s DeepRacer, MIT’s Duckiebot, iRobot’s Create-2, and Thymio. The top group includes robots based on RC trucks; the bottom group includes navigation robots for deployment at scale and in education. Note that the cost of the smartphone needed for OpenBot is not included in this comparison.
If you’d like an OpenBot of your own, you don’t need to know all that much about robotics hardware or software. For the hardware, you probably need some basic mechanical and electronics experience—think Arduino project level. The software is a little more complicated; there’s a pretty good walkthrough to get some relatively sophisticated behaviors (like autonomous person following) up and running, but things rapidly degenerate into a command line interface that could be intimidating for new users. We did ask about why OpenBot isn’t ROS-based to leverage the robustness and reach of that community, and Muller said that ROS “adds unnecessary overhead,” although “if someone insists on using ROS with OpenBot, it should not be very difficult.”
Without building OpenBot to explicitly be part of an existing ecosystem, the challenge going forward is to make sure that the project is consistently supported, lest it wither and die like so many similar robotics projects have before it. “We are committed to the OpenBot project and will do our best to maintain it,” Mueller assures us. “We have a good track record. Other projects from our group (e.g. CARLA, Open3D, etc.) have also been maintained for several years now.” The inherently open source nature of the project certainly helps, although it can be tricky to rely too much on community contributions, especially when something like this is first starting out.
The OpenBot folks at Intel, we’re told, are already working on a “bigger, faster and more powerful robot body that will be suitable for mass production,” which would certainly help entice more people into giving this thing a go. They’ll also be focusing on documentation, which is probably the most important but least exciting part about building a low-cost community focused platform like this. And as soon as they’ve put together a way for us actual novices to turn our phones into robots that can do cool stuff for cheap, we’ll definitely let you know. Continue reading
Posted in Human Robots
#437603 Throwable Robot Car Always Lands on Four ...
Throwable or droppable robots seem like a great idea for a bunch of applications, including exploration and search and rescue. But such robots do come with some constraints—namely, if you’re going to throw or drop a robot, you should be prepared for that robot to not land the way you want it to land. While we’ve seen some creative approaches to this problem, or more straightforward self-righting devices, usually you’re in for significant trade-offs in complexity, mobility, and mass.
What would be ideal is a robot that can be relied upon to just always land the right way up. A robotic cat, of sorts. And while we’ve seen this with a tail, for wheeled vehicles, it turns out that a tail isn’t necessary: All it takes is some wheel spin.
The reason that AGRO (Agile Ground RObot), developed at the U.S. Military Academy at West Point, can do this is because each of its wheels is both independently driven and steerable. The wheels are essentially reaction wheels, which are a pretty common way to generate forces on all kinds of different robots, but typically you see such reaction wheels kludged onto these robots as sort of an afterthought—using the existing wheels of a wheeled robot is a more elegant way to do it.
Four steerable wheels with in-hub motors provide control in all three axes (yaw, pitch, and roll). You’ll notice that when the robot is tossed, the wheels all toe inwards (or outwards, I guess) by 45 degrees, positioning them orthogonal to the body of the robot. The front left and rear right wheels are spun together, as are the front right and rear left wheels. When one pair of wheels spins in the same direction, the body of the robot twists in the opposite way along an axis between those wheels, in a combination of pitch and roll. By combining different twisting torques from both pairs of wheels, pitch and roll along each axis can be adjusted independently. When the same pair of wheels spin in directions opposite to each other, the robot yaws, although yaw can also be derived by adjusting the ratio between pitch authority and roll authority. And lastly, if you want to sacrifice pitch control for more roll control (or vice versa) the wheel toe-in angle can be changed. Put all this together, and you get an enormous amount of mid-air control over your robot.
Image: Robotics Research Center/West Point
The AGRO robot features four steerable wheels with in-hub motors, which provide control in all three axes (yaw, pitch, and roll).
According to a paper that the West Point group will present at the 2020 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), the overall objective here is for the robot to reach a state of zero pitch or roll by the time the robot impacts with the ground, to distribute the impact as much as possible. AGRO doesn’t yet have a suspension to make falling actually safe, so in the short term, it lands on a foam pad, but the mid-air adjustments it’s currently able to make result in a 20 percent reduction of impact force and a 100 percent reduction in being sideways or upside-down.
The toss that you see in the video isn’t the most aggressive, but lead author Daniel J. Gonzalez tells us that AGRO can do much better, theoretically stabilizing from an initial condition of 22.5 degrees pitch and 22.5 degrees roll in a mere 250 milliseconds, with room for improvement beyond that through optimizing the angles of individual wheels in real time. The limiting factor is really the amount of time that AGRO has between the point at which it’s released and the point at which it hits the ground, since more time in the air gives the robot more time to change its orientation.
Given enough height, the current generation of AGRO can recover from any initial orientation as long as it’s spinning at 66 rpm or less. And the only reason this is a limitation at all is because of the maximum rotation speed of the in-wheel hub motors, which can be boosted by increasing the battery voltage, as Gonzalez and his colleagues, Mark C. Lesak, Andres H. Rodriguez, Joseph A. Cymerman, and Christopher M. Korpela from the Robotics Research Center at West Point, describe in the IROS paper, “Dynamics and Aerial Attitude Control for Rapid Emergency Deployment of the Agile Ground Robot AGRO.”
Image: Robotics Research Center/West Point
AGRO 2 will include a new hybrid wheel-leg and non-pneumatic tire design that will allow it to hop up stairs and curbs.
While these particular experiments focus on a robot that’s being thrown, the concept is potentially effective (and useful) on any wheeled robot that’s likely to find itself in mid-air. You can imagine it improving the performance of robots doing all sorts of stunts, from driving off ramps or ledges to being dropped out of aircraft. And as it turns out, being able to self-stabilize during an airdrop is an important skill that some Humvees could use to keep themselves from getting tangled in their own parachute lines and avoid mishaps.
Before they move on to Humvees, though, the researchers are working on the next version of AGRO named AGRO 2. AGRO 2 will include a new hybrid wheel-leg and non-pneumatic tire design that will allow it to hop up stairs and curbs, which sounds like a lot of fun to us. Continue reading
Posted in Human Robots