{"id":6070,"date":"2015-07-03T09:00:12","date_gmt":"2015-07-03T13:00:12","guid":{"rendered":"https:\/\/blogs.mathworks.com\/pick\/?p=6070"},"modified":"2015-07-02T13:04:35","modified_gmt":"2015-07-02T17:04:35","slug":"testing-safety-critical-control-systems","status":"publish","type":"post","link":"https:\/\/blogs.mathworks.com\/pick\/2015\/07\/03\/testing-safety-critical-control-systems\/","title":{"rendered":"Testing Safety Critical Control Systems"},"content":{"rendered":"<div xmlns:mwsh=\"https:\/\/www.mathworks.com\/namespace\/mcode\/v1\/syntaxhighlight.dtd\" class=\"content\">\r\n   <introduction>\r\n      <p><a href=\"https:\/\/www.mathworks.com\/matlabcentral\/profile\/authors\/3208495\">Sean<\/a>'s pick this week is <a href=\"https:\/\/www.mathworks.com\/matlabcentral\/fileexchange\/39047-testing-safety-critical-control-systems\">Testing of Safety Critical Control Systems<\/a> by <a href=\"https:\/\/www.mathworks.com\/matlabcentral\/profile\/authors\/2222682\">Yogananda Jeppu<\/a>.\r\n      <\/p>\r\n   <\/introduction>\r\n   <p>With the loss of the SpaceX Falcon 9 last week it seems like an appropriate time to read through Yogananda's compilation of\r\n      many possible failures and mitigations in a control system.  The cause of the failure for the SpaceX Falcon is not yet publicly\r\n      known so it will be interesting to hear what their engineers discover.\r\n   <\/p>\r\n   <p><img decoding=\"async\" vspace=\"5\" hspace=\"5\" src=\"https:\/\/blogs.mathworks.com\/images\/pick\/Sean\/mainsafetycritical\/spacex.png\"> <\/p>\r\n   <p>In this document, Yogananda has covered a wide variety of accidents and their causes, possible failures in specific parts\r\n      of a control system, how to identify and circumvent these potential failures and tips from his experiences.\r\n   <\/p>\r\n   <p>The most recent update to this slide deck, includes a bit on Simulink Design Verifier and formal methods.  I'll be curious\r\n      to see if he extends it to include examples using <a href=\"https:\/\/www.mathworks.com\/products\/polyspace-code-prover\/\">Polyspace Code Prover<\/a> which uses formal methods and static analysis to prove the lack (or presence!) of run-time errors in C\/C++ code.  For example:\r\n   <\/p>\r\n   <p><img decoding=\"async\" vspace=\"5\" hspace=\"5\" src=\"https:\/\/blogs.mathworks.com\/images\/pick\/Sean\/mainsafetycritical\/polyspace.png\"> <\/p>\r\n   <h3>Comments<a name=\"2\"><\/a><\/h3>\r\n   <p>Do you design, test, or research failures in safety critical control systems?  If so, are there any other insights that you\r\n      would like to share?\r\n   <\/p>\r\n   <p>Give it a read and let us know what you think <a href=\"https:\/\/blogs.mathworks.com\/pick\/?p=6070#respond\">here<\/a> or leave a <a href=\"https:\/\/www.mathworks.com\/matlabcentral\/fileexchange\/39047-testing-safety-critical-control-systems#comments\">comment<\/a> for Yogananda.\r\n   <\/p><script language=\"JavaScript\">\r\n<!--\r\n\r\n    function grabCode_91ba22e387764e18871f0a84f39dec36() {\r\n        \/\/ Remember the title so we can use it in the new page\r\n        title = document.title;\r\n\r\n        \/\/ Break up these strings so that their presence\r\n        \/\/ in the Javascript doesn't mess up the search for\r\n        \/\/ the MATLAB code.\r\n        t1='91ba22e387764e18871f0a84f39dec36 ' + '##### ' + 'SOURCE BEGIN' + ' #####';\r\n        t2='##### ' + 'SOURCE END' + ' #####' + ' 91ba22e387764e18871f0a84f39dec36';\r\n    \r\n        b=document.getElementsByTagName('body')[0];\r\n        i1=b.innerHTML.indexOf(t1)+t1.length;\r\n        i2=b.innerHTML.indexOf(t2);\r\n \r\n        code_string = b.innerHTML.substring(i1, i2);\r\n        code_string = code_string.replace(\/REPLACE_WITH_DASH_DASH\/g,'--');\r\n\r\n        \/\/ Use \/x3C\/g instead of the less-than character to avoid errors \r\n        \/\/ in the XML parser.\r\n        \/\/ Use '\\x26#60;' instead of '<' so that the XML parser\r\n        \/\/ doesn't go ahead and substitute the less-than character. \r\n        code_string = code_string.replace(\/\\x3C\/g, '\\x26#60;');\r\n\r\n        author = 'Sean de Wolski';\r\n        copyright = 'Copyright 2015 The MathWorks, Inc.';\r\n\r\n        w = window.open();\r\n        d = w.document;\r\n        d.write('<pre>\\n');\r\n        d.write(code_string);\r\n\r\n        \/\/ Add author and copyright lines at the bottom if specified.\r\n        if ((author.length > 0) || (copyright.length > 0)) {\r\n            d.writeln('');\r\n            d.writeln('%%');\r\n            if (author.length > 0) {\r\n                d.writeln('% _' + author + '_');\r\n            }\r\n            if (copyright.length > 0) {\r\n                d.writeln('% _' + copyright + '_');\r\n            }\r\n        }\r\n\r\n        d.write('<\/pre>\\n');\r\n      \r\n      d.title = title + ' (MATLAB code)';\r\n      d.close();\r\n      }   \r\n      \r\n-->\r\n<\/script><p style=\"text-align: right; font-size: xx-small; font-weight:lighter;   font-style: italic; color: gray\"><br><a href=\"javascript:grabCode_91ba22e387764e18871f0a84f39dec36()\"><span style=\"font-size: x-small;        font-style: italic;\">Get \r\n            the MATLAB code \r\n            <noscript>(requires JavaScript)<\/noscript><\/span><\/a><br><br>\r\n      Published with MATLAB&reg; R2015b<br><\/p>\r\n<\/div>\r\n<!--\r\n91ba22e387764e18871f0a84f39dec36 ##### SOURCE BEGIN #####\r\n%% Testing Safety Critical Control Systems\r\n%\r\n% <https:\/\/www.mathworks.com\/matlabcentral\/profile\/authors\/3208495 Sean>'s\r\n% pick this week is\r\n% <https:\/\/www.mathworks.com\/matlabcentral\/fileexchange\/39047-testing-safety-critical-control-systems Testing of\r\n% Safety Critical Control Systems> by\r\n% <https:\/\/www.mathworks.com\/matlabcentral\/profile\/authors\/2222682 Yogananda\r\n% Jeppu>.\r\n% \r\n\r\n%% \r\n% With the loss of the SpaceX Falcon 9 last week it seems like an\r\n% appropriate time to read through Yogananda's compilation of many possible\r\n% failures and mitigations in a control system.  The cause of the failure\r\n% for the SpaceX Falcon is not yet publicly known so it will be interesting\r\n% to hear what their engineers discover.\r\n%\r\n% <<spacex.png>>\r\n%\r\n% In this document, Yogananda has covered a wide variety of accidents and\r\n% their causes, possible failures in specific parts of a control system,\r\n% how to identify and circumvent these potential failures and tips from\r\n% his experiences.\r\n%\r\n% The most recent update to this slide deck, includes a bit on Simulink\r\n% Design Verifier and formal methods.  I'll be curious to see if he extends\r\n% it to include examples using\r\n% <https:\/\/www.mathworks.com\/products\/polyspace-code-prover\/ Polyspace Code\r\n% Prover> which uses formal methods and static analysis to prove the lack\r\n% (or presence!) of run-time errors in C\/C++ code.  For example:\r\n%\r\n% <<polyspace.png>>\r\n\r\n%% Comments \r\n% Do you design, test, or research failures in safety critical control\r\n% systems?  If so, are there any other insights that you would like to\r\n% share?\r\n%\r\n% Give it a read and let us know what you think\r\n% <https:\/\/blogs.mathworks.com\/pick\/?p=6070#respond here> or leave a\r\n% <https:\/\/www.mathworks.com\/matlabcentral\/fileexchange\/39047-testing-safety-critical-control-systems#comments\r\n% comment> for Yogananda.\r\n \r\n\r\n##### SOURCE END ##### 91ba22e387764e18871f0a84f39dec36\r\n-->","protected":false},"excerpt":{"rendered":"<div class=\"overview-image\"><img decoding=\"async\"  class=\"img-responsive\" src=\"https:\/\/blogs.mathworks.com\/images\/pick\/Sean\/mainsafetycritical\/spacex.png\" onError=\"this.style.display ='none';\" \/><\/div><p>\r\n   \r\n      Sean's pick this week is Testing of Safety Critical Control Systems by Yogananda Jeppu.\r\n      \r\n   \r\n   With the loss of the SpaceX Falcon 9 last week it seems like an appropriate... <a class=\"read-more\" href=\"https:\/\/blogs.mathworks.com\/pick\/2015\/07\/03\/testing-safety-critical-control-systems\/\">read more >><\/a><\/p>","protected":false},"author":87,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[29,16],"tags":[],"_links":{"self":[{"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/posts\/6070"}],"collection":[{"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/users\/87"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/comments?post=6070"}],"version-history":[{"count":3,"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/posts\/6070\/revisions"}],"predecessor-version":[{"id":6073,"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/posts\/6070\/revisions\/6073"}],"wp:attachment":[{"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/media?parent=6070"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/categories?post=6070"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.mathworks.com\/pick\/wp-json\/wp\/v2\/tags?post=6070"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}