IT Outage at British Airways Causes Cancelled Flights

NBC News reports here on an information technology (IT) outage at British Airways that caused them to suspend operations at Heathrow and Gatwick.

The Fuzzy Line Between Information Technology and Cyber-Physical Systems

NBC News reports here on a pair of computer problems that have caused flight delays.  In the past few months, both Delta and Southwest suffered computer problems that severely disrupted their flight operations.<p>
These problems were all related to information technology (IT)---traditional issues related to databases, networks, etc.  Nonetheless, they disrupted the physical plants of the airlines in the form of flight delays.  We often treat CPS and IT as separate domains but in the real world they blend together.<p>
Many utilities separate their billing and management IT systems from their computer systems that operate equipment.  Nonetheless, these systems must talk---you can't bill unless you know something about the equipment's operation.  And the operational computer systems that perform cyber-physical operations such as control make extensive use of hardware and software originally designed for IT.
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A chain is only as strong as its weakest link.  If we want to build safe and secure cyber-physical systems, we need to be sure that IT and CPS work together.

Lessons from History on Autonomous Vehicles and ADAS

Many commentators refer to the surge commercial interest in automated driver assistance systems (ADAS) and autonomous vehicles as amazing, which is entirely true.  But many also refer to ADAS and autonomous vehicles as unprecedented, which is not so true.
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One key concern for completely autonomous vehicles---those for which the passengers have no vehicle controls whatsoever---is how to mix them with driven vehicles and pedestrians.  We have seen before a mixture of vastly different vehicles, namely at the dawn of the automotive age.  Cars and trucks co-existed with horses and horse-drawn vehicles for several decades.  This was a difficult combination and one that bears a surprising resemblance to the mixture of autonomous and driven vehicles.  Horses are, after all, ultimately autonomous, something that becomes clear once you mount a horse and start to ride.  Silent motion pictures give us glimpses into this world.  Many silent pictures were filmed on the streets without benefit of modern film permits.  As a result, they captured typical interactions between motorized and horse-drawn vehicles.
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ADAS has clear precedent in aviation.  Airbus airliners have for several decades been full-authority control systems---the controls do not always respond to the pilot's command if the control system believes that those commands are dangerous.   The Boeing 787 is also a full-authority control system. These planes have been involved in accidents that can be attributed, at least in part, on their control systems.  Even in the absence of accidents, a long-standing concern about these control systems is that they allow the pilot's attention to lapse, resulting in longer response times by the pilot in the case of something happening.
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Perhaps the car companies are studying these historical precedents internally.  I certainly hope so.  We need to learn as much from history as we can in order to make the new generation of vehicles as safe as they can be.

NTSB Report on 787 Battery Fire

I just found this link to the NTSB report on the 2013 battery fire aboard a JAL 787.

Hello, Mechanical Sewing Machine

 I have written several posts about the trials of finding a good sewing machine.  I finally decided to buy an industrial model.  The store owner told me that it would last 20 years.  I think that he underestimates.  The way this machine is built, I plan to leave it in my will.  I mention it here as an example of heavy-duty design.  So much modern software and electronics are designed to be throw-away; the modern smartphone is designed to last for 2-3 years.  While disposable devices certainly have their place, I hope that we don't lose the ability to design solid, long-lasting devices.


English is not the first language of the manual.


This machine has an oil pan.  It uses splash lubrication just like a car engine. The lubricant is mineral oil.  It has a sweet smell and should stain less in the unlikely case that it spills.  I have read quite a few complaints on the Web about the plastic gears used in portable sewing machines and other home appliances.  As I understand it, plastic gears perform better in lubrication-free environments; I don't think the average homeowner wants to oil all their appliances.  I'd rather have good plastic gears than cheap metal gears.  But the drivetrain of this machine is impressively solid.

The speed control connection to the motor is a steel rod. The pedal on my portable machine proudly proclaims "Electronic."  No wimpy electronic control here.

This machine came with a servo motor. Older machines use clutch motors, which must have been both loud and a little smelly. This machine runs at 5000 stitches per minute---that's 25 meters per minute.  The knob on the motor allows you to set the maximum speed to a lower value.  I was a little worried about the sensitivity of the speed control, but it has proven to be easy to control.

You say you want vibration control? Just the head of this machine weighs 75 pounds.  Add in the motor and table and it tips in at over 100 pounds. That's vibration control technology straight from Sir Isaac Newton---a 100 pound body at rest tends to stay at rest.

This machine only makes one stitch, a straight stitch. It is also mechanically set for medium-weight fabric. To adjust it for either very light or very heavy fabrics, I have to use a screwdriver to adjust the feed dogs that feed the fabric. I also have to adjust the thread tension by hand.  Home portable machines have sensors and controllers that automatically adjust all aspects of the machine to adapt to the fabric conditions.  They also perform a lot of different stitches; high-end machines may perform hundreds of decorative stitches.  But their stitches aren't as uniform as the ones produced by industrial machines.  Building a machine to do one thing well has advantages.

Hello, Cyber-Physical Sewing Machine

The gearbox on my mechanical sewing machine broke.  It sounded like it was mixing gravel; I didn't investigate further.  I decided to replace it with a cyber-physical model but one that didn't have a lot of features that I wouldn't use.  I think this model will have a strong drivetrain as well as fairly reliable electronics, but only time will tell.
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My first sewing machine suffered an electronics failure, and a rather mundane one at that.  As we integrate electronics and computers into all sorts of devices, I hope that system designers keep in mind that consumer electronics devices (cell phones, audio players, etc.) are designed with very short lifespans in mind.  In contrast, many of the cyber-physical devices, such as sewing machines, have much longer lifespans.  All the components should be designed to have consistent lifespans.  This means building printed circuit boards and chips to higher quality standards than those to which the electronics industry has become accustomed.  And, of course, more components of any type means more opportunities for failure.

DAC special session on cyber-physical systems

The Design Automation Conference is coming to the Moscone Center in San Francisco during the week of June 7.  Mohammed Al Faruque and I have organized a special session on cyber-physical systems architectures and methodologies; it will take place Wednesday, JUne 10, from 1:30 to 3 PM.  The session will feature three talks: I will give the introductory talk; Janos Sztipanovits from Vanderbilt will talk about their experience with CPS tool chains; and Rajesh Gupta will discuss models, abstractions, and architectures.  You can find the program here.