HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Senerjp
User Rank
Iron
Re: Definitely a trend to watch
Senerjp   10/4/2011 10:18:46 AM
NO RATINGS
Two controllers, if they are truly ustilizing multi-pathing, would actually act in parallel and would be more reliable. R = 1-(1-R)^n so to the extent they are completely seperate ( which nothing ever truly is) they would approximate R=.9999!

Ivan Kirkpatrick
User Rank
Platinum
Definitely a trend to watch
Ivan Kirkpatrick   10/3/2011 10:00:20 AM
NO RATINGS
I can see a lot of advantages in multicore processors like these.  I wonder though about the fault tolerance for a device that uses two cores and compares the results?  I would think 3 cores and voting the odd one out might be slightly more expensive but better.  Along those same lines the fault tolerance and ability to function in a degraded state might be really useful as well.  Sensor failure or errors related to the sensors need to be accommodated as well in a fault tolerant manner.

I am a bit leary of simply adding in more redundancy.  That can also lead to more failures.  Correct me if I am wrong but 2 controllers with 99% reliability each when coupled are they not then 98% reliable?

In general I learned it was better to design systems with greater reliability, test it and prove it historically in production.  Then only add additional redundancy if it was really required.  Some systems required redundancy as a matter of course in terms of availability for maintenance and mission critical applications.  Perhaps others can weigh in on this and explain this subject a little better.  

I suppose part of this is the diffference between redundant and backup components?  When I served on US Navy ships we had three steam driven turbogenerators for redundancy and a diesel generator for backup.  But we had only one main engine.  I know the costs figure into this as well as they always do.



Partner Zone
Latest Analysis
It's been two years since the Mac Mini's last appearance on iFixit's teardown table, but a newly revised version joins Apple's lineup this week.
More often than not, with the purchase of a sports car comes the sacrifice of any sort of utility. In other words, you can forget about a large trunk, extra seats for the kids, and more importantly driving in snowy (or inclement) weather. But what if there was a vehicle that offered the best of both worlds; great handling and practicality?
Kevin Gautier of Formlabs describes the making of a carbon fiber mold for an intake manifold, using a $3,300 3D printer, during Medical Design & Manufacturing Midwest.
Science fiction author Isaac Asimov may have the best rules for effective brainstorming and creativity. His never-before-published essay, "On Creativity," recently made it to the Web pages of MIT Technology Review.
Much has been made over the potentially dangerous flammability of lithium-ion batteries after major companies like Boeing, Sony, and Tesla have grappled with well-publicized battery fires. Researchers at Stanford University may have come up with a solution to this problem with a smart sensor for lithium-ion batteries that provides a warning if the battery is about to overheat or catch fire.
More:Blogs|News
Design News Webinar Series
10/7/2014 8:00 a.m. California / 11:00 a.m. New York
9/25/2014 11:00 a.m. California / 2:00 p.m. New York
9/10/2014 11:00 a.m. California / 2:00 p.m. New York
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Oct 20 - 24, How to Design & Build an Embedded Web Server: An Embedded TCP/IP Tutorial
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: 10/28-10/30 11:00 AM
Sponsored by Stratasys
Next Class: 10/28-10/30 2:00 PM
Sponsored by Gates Corporation
Next Class: 11/11-11/13 2:00 PM
Sponsored by Littelfuse
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service