{"id":75593,"date":"2023-11-09T14:59:44","date_gmt":"2023-11-09T19:59:44","guid":{"rendered":"http:\/\/www.bu.edu\/cas\/?post_type=r_cas_magazine&#038;p=75593"},"modified":"2023-11-27T15:55:10","modified_gmt":"2023-11-27T20:55:10","slug":"faster-safer-smarter","status":"publish","type":"r_cas_magazine","link":"https:\/\/www.bu.edu\/cas\/arts-sciences\/2023\/faster-safer-smarter\/","title":{"rendered":"Faster, Safer, Smarter"},"content":{"rendered":"<p class=\"byline\">By Mara Sassoon | Photos by Doug Levy<\/p>\n<p>On a recent morning in <a href=\"http:\/\/cpslab.bu.edu\/\">Renato Mancuso\u2019s lab<\/a>, remote controls, a miniature car, and a collection of blue-propellered quadrotor drones are scattered across a long workbench. Lab members tinker with glinting green circuit boards at their computer stations. All of these items are part of the lab\u2019s goal of improving computer systems that \u201cinteract with the physical world and that we rely on to carry on our modern lifestyle,\u201d says <a href=\"https:\/\/www.bu.edu\/cs\/profiles\/renato-mancuso\/\">Mancuso<\/a>, an assistant professor of computer science.<\/p>\n<p>We come across many cyber-physical systems in our daily lives. The computer that controls a washing machine is one example\u2014it uses inputs, like the type of clothing you are washing or the water temperature you\u2019d like to use, and has sensors that activate water valves and heating elements. The computer directs what the machine does with your clothing. But Mancuso and the members of his Cyber-Physical Systems Lab, in BU\u2019s Center for Computing &amp; Data Sciences, aren\u2019t interested in washing machines; they are focused on <em>safety-critical<\/em> cyber-physical systems\u2014for example, the systems that control planes and cars, both manned and autonomous\u2014and ensure they operate safely and efficiently.<\/p>\n<p>\u201cEven a regular non-self-driving car is pretty much a computer on wheels\u2014and we entrust our lives to them,\u201d Mancuso says. All of the projects in his lab are aimed at developing safer, more efficient, and more cost-effective cyber-physical systems. \u201cNASA can afford to spend billions of dollars to create a rover and custom build their [computer] chips to make sure that rover can survive 100 sols on Planet X,\u201d explains Mancuso. \u201cBut if we\u2019re talking about bringing safe, autonomous driving to the masses, we\u2019ll want to do that with commercial systems off the shelf. My approaches are targeting this kind of application where we want high-assurance cyber-physical systems that can be built without spending billions of dollars.\u201d<\/p>\n<h2>Time Is of the Essence<\/h2>\n<p>Recent headlines show the perils of safety-critical system failures. A Norfolk Southern freight train transporting toxic chemicals derailed in East Palestine, Ohio, in February 2023, causing a fire and a chemical spill. The National Transportation Safety Board\u2019s preliminary report on the derailment found that crew members weren\u2019t alerted to an overheated wheel bearing quickly enough. Then, in March 2023, another Norfolk Southern train derailed outside Springfield, Ohio.<\/p>\n<p>Autonomous cars have also had their share of incidents. In June 2023, <a href=\"https:\/\/www.washingtonpost.com\/technology\/2023\/06\/10\/tesla-autopilot-crashes-elon-musk\/\">the <em>Washington Post<\/em> reported<\/a> that, according to National Highway Traffic Safety Administration data, Teslas in \u201cautopilot mode\u201d were involved in more than 700 crashes, including 17 fatal accidents, since 2019. The article cited one accident that occurred in North Carolina in March 2023, in which a Tesla allegedly in \u201cautopilot mode\u201d and going 45 mph failed to brake, striking and injuring a teen getting off a school bus.<\/p>\n<p>These incidents emphasize the importance of a key focus of Mancuso\u2019s research: timeliness. Take a car that is supposed to sense an obstacle and apply braking. \u201cIn testing that, it\u2019s not enough that it detects that there is a kid-size mannequin on the road. It also has to be sure to brake on time,\u201d says Mancuso. Airbag deployment is another example of the importance of timing. If it deploys too late, then there is a risk of the driver hitting the steering wheel; too early, and the airbag is already partially deflated by the time the driver lands on it.<\/p>\n<blockquote>\n<p class=\"p1\">A regular non-self-driving car is pretty much a computer on wheels\u2014and we entrust our lives to them.<\/p>\n<p class=\"byline\">Renato Mancuso<\/p>\n<\/blockquote>\n<p>Much of the research in Mancuso\u2019s lab is concerned with narrowing the right window of time for an action to be performed. \u201cOur mission is: Can we guarantee that strong temporal requirements can be met in spite of the increasing complexity of both the software and the hardware in platforms?\u201d he says.<\/p>\n<p>To accomplish that, Mancuso and his students work at the intersection of software and hardware, attempting to improve a system\u2019s context awareness (knowing what\u2019s going on in the environment around it) and self-awareness (knowing what is going on inside itself) without sacrificing, and even improving, timeliness.<\/p>\n<p>\u201cWith self-awareness, the system becomes capable of knowing that we are running behind schedule or that we are on track,\u201d says Mancuso, a <a href=\"https:\/\/www.bu.edu\/cs\/2023\/08\/29\/renato-mancuso-awarded-nsf-career-grant\/\">National Science Foundation CAREER award recipient<\/a>. \u201cWith context awareness in a cyber-physical system, we want to know if a temperature is too high compared to what we expected, or if there are humans around, or perhaps if we are at a certain altitude or going a certain airspeed\u2014properties of the physical world that we have to react to.\u201d In order to create systems that are smarter and have better context awareness, he says, using simple sensors doesn\u2019t quite cut it anymore. \u201cWe need cameras, we need things that can give us a more comprehensive understanding of the surrounding space.\u201d But building these smarter, more aware systems also requires more complex computers, which can result in added processing time.<\/p>\n<p>Mancuso is working to create ways for complex, high-performance systems to achieve self-awareness. His lab has been looking into how crucial information about the temporal behavior of applications can be accessed in systems that include something called field programmable gate array (FPGA), a reprogrammable hardware. Francesco Ciraolo (GRS\u201929,\u201929) describes it as a \u201chardware scratch pad, where you can build anything on it.\u201d<\/p>\n<p>In a study, coauthored with PhD student Shahin Roozkhosh (GRS\u201925,\u201925) and Denis Hoornaert, a researcher at the Technical University of Munich, Mancuso found that FPGA can be used to \u201clie\u201d in order to gain control over its temporal properties and access data more quickly. \u201cIt\u2019s called CAESAR because it\u2019s a technique we call coherence backstabbing\u2014it\u2019s basically betraying something called a coherence protocol that the CPU [central processing unit] plays when it accesses memory,\u201d says Mancuso.<\/p>\n<figure id=\"attachment75594\" aria-describedby=\"caption-attachment75594\" style=\"width: 1210px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" src=\"\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped.jpg\" alt=\"Mancuso holding a drone in his lab\" width=\"1200\" height=\"1552\" class=\"size-full wp-image-75594\" srcset=\"https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped.jpg 1200w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-492x636.jpg 492w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-792x1024.jpg 792w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-768x993.jpg 768w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-1188x1536.jpg 1188w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-755x976.jpg 755w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-320x414.jpg 320w, https:\/\/www.bu.edu\/cas\/files\/2023\/11\/23-1416-CASMANCUSO-003-cropped-620x802.jpg 620w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><figcaption id=\"caption-attachment75594\" class=\"wp-caption-text\">Mancuso\u2019s lab is concerned with the timeliness of cyber-physical systems\u2014which ensures that safety features are triggered within the optimal period of time.<\/figcaption><\/figure>\n<p>With a coherence protocol, instead of trying to access stored memory that might be located far away and take time to retrieve, the system checks if other CPUs closer by have that piece of memory. However, Mancuso, winner of BU\u2019s 2023 Gitner Award for Innovation in Teaching with Technology, and his team of researchers were able to demonstrate that an FPGA is capable of accessing memory faster. By programming the FPGA a certain way, Mancuso says, \u201cif the message \u2018Hey, do you have this piece of data?\u2019 comes into the FPGA, it can flat out lie about it and say, \u2018Yes, I have it.\u2019 So, that piece of data doesn\u2019t have to be in memory; [the FPGA] can make it up or go and fetch it from a local, faster memory, and maybe patch it up and take out information it doesn\u2019t want to pass along and then send that to the CPU.\u201d According to Mancuso, with the ability to \u201cbackstab\u201d this protocol, his lab is able to redefine what it means to access data. \u201cNow, access to data is programmable. We can define what the data is and how long it takes to get it.\u201d<\/p>\n<p>Mancuso is trying to push the boundaries of what is controllable in cyber-physical systems. \u201cWe are pioneering these new techniques that allow you to say the timing of memory is not beyond your control anymore. Everything is in your hands if you want to play with it.\u201d<\/p>\n<h2>\u201cA Godlike Entity\u201d<\/h2>\n<p>Mancuso and his lab have been working on another project, that factors cost-effectiveness into their research.<\/p>\n<p>Typically, industrial systems have a special circuitry that is attached externally and is used for debugging\u2014monitoring what is happening within, such as if an application is running slowly, says Mancuso. But that external circuitry is costly.<\/p>\n<p>\u201cYou normally attach up to $25,000 worth of equipment to a special port,\u201d he says. With this project, however, his students found that the expensive external debugger is unnecessary. Rather, that kind of application monitoring and debugging can happen online and within the system. \u201cOur technique basically works at the level of operating system and firmware and is able to track live what\u2019s happening to your application. It\u2019s able to tell you, \u2018Yep, you have reached this milestone in your progress, and you\u2019re here earlier than expected, so everything is fine.\u2019 Or, \u2018You\u2019re here later than expected, and maybe these are the reasons,\u2019 so you can run a little diagnostic.\u201d<\/p>\n<p>He compares it to the services navigation apps have provided people. \u201cWhen you need to get to a train station, which in this case we\u2019re comparing to the completion of an application, you\u2019re not just happy with knowing you need to get there, but you want to get an estimate of how long it takes, and as you go forward, you want to know if you\u2019re on track or not\u2014will you be there 10 minutes early or 20 minutes late?\u201d he says.<\/p>\n<p>\u201cWe can hit the brakes on other things in the system and allow this application to speed up and catch up with [the intended] progress. We can do it over and over again, slowing down and speeding up until we achieve the point by when we want to come.\u201d<\/p>\n<hr \/>\n<p><a href=\"https:\/\/www.bu.edu\/cas\/arts-sciences\/2023\/\" class=\"button-primary\">Back to full issue<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Computer scientist Renato Mancuso wants to improve the systems that control our vehicles and devices<\/p>\n","protected":false},"featured_media":75598,"template":"","department":[],"_links":{"self":[{"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/magazine-articles\/75593"}],"collection":[{"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/magazine-articles"}],"about":[{"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/types\/r_cas_magazine"}],"version-history":[{"count":13,"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/magazine-articles\/75593\/revisions"}],"predecessor-version":[{"id":76019,"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/magazine-articles\/75593\/revisions\/76019"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/media\/75598"}],"wp:attachment":[{"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/media?parent=75593"}],"wp:term":[{"taxonomy":"r_cas_department","embeddable":true,"href":"https:\/\/www.bu.edu\/cas\/wp-json\/wp\/v2\/department?post=75593"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}