RELAVENCE

April 23, 2014


The first two paragraphs are taken from: “WISDOM TO GO”.  By Dr. Elizabeth Taylor

Members of the northern Natal tribes of South African greet one another daily by saying “Sawa bona”, which literally means: “I see you.” The response is “Sikhona” which means: “I am here”. This exchange is important, for it denotes that ‘until you ‘see’ me, I do not exist; and when you ‘see’ me, you bring me into existence. Members of these tribes go about their day with this personal validation from everyone they encounter – seen for who they are.  This speaks to the powerful intrinsic human need for validation, which we all share.  Compared to greetings in American and most western cultures this kind of deep acknowledgement of the ‘other’ on a daily basis is far more humane and vital, and it supports the wellbeing and integrity of the human community.  Our western way of saying “Hello.  How are you?” lacks this presence – this depth.  Often we greet in an automatic and rather perfunctory way, not really paying attention to the other’s response.  Ready to rush on once the greeting leaves our lips.  But the response we get may very well be “Well I’m not doing so great”.  We expect and assume a standard and predictable retort from the ‘other’, such as “I’m fine, and you?”which keeps us comfortable and not requiring any further effort or engagement on our part. Too often our greetings are not meant to go any deeper than superficial pleasantries.  We hear what we want to hear because we don’t want to or have time to engage at deeper levels.  We generally are not comfortable with and avoid those kinds of openings and intrigues.

What we stand to learn from the South African tribes is the importance of being ‘present’ with every person we greet during each day.  Our presence with them validates their humanity – which in-turn validates our own humanity.  We must watch and manage our tendency to rush through greetings, our tendency to not really ‘see’ or listen to others as they share their points of view or frames of thought.  We must monitor our tendency to get busy formulating assumptions and rebuttals while watching the other person’s lips move; and our tendency to impose criticism or even advice when it is not invited. These are forms of abuse, which often leaves the ‘other’ feeling bereft, assailed or treated in some unseemly way and embodying a vague sense of ‘dis-ease’ from a simple personal exchange. Moreover, these unsound feelings interfere with one’s further interactions, because this leftover ‘hurt’ energy must be relieved and acted out in some way.

These are definitely words of wisdom.  My wife and I are care-givers for a ninety-one (91) year old father (mine) and a ninety-four (94) year old mother (my wife’s).  Even though they are senior citizens plus, each requires the daily validation a visit and/or a phone call brings.  This validation is not age-dependent.  Even infants need validation given them by loving and caring parents for the best shot at a normal life.  This past week nine (9) individuals, some children, were murdered in Chicago with forty-seven (47) individuals injured.  The gunfire resulted from gang members squaring off at each other.  Turf wars to be exact.  Grievances unresolved.    The philologists tell us gang members, usually young men, gather together for the validation not found at home within a strong family unit.  Their family is represented by the peer group they choose to associate with.  I think so much is lost when proper encouragement of a positive nature is not given nor received; not just by the “gangs of Chicago”, but by individuals we meet on a daily basis.

I would challenge everyone to live, not just say “sawa bona” to those we see on a daily basis—friend, family or stranger.  We all deserve and need validation. I welcome your comments.


SAFETY  WHEN USING ROBOTIC SYSTEMS:

If you follow my posting you know that I am definitely interested in robotic systems and robots themselves.   Robots represent a very interesting position in manufacturing and one that has it’s own safety rules.  This post strives to provide a brief checklist relative to the systems themselves. 

Over the past ten to fifteen years we have seen a remarkable increase in the use of robotic systems to automate manufacturing processes.  Various industries rely heavily on robotic systems for smooth and continuous operation.   Today, major technological advances,  including microprocessors, artificial intelligence techniques, and innovations in automation and control systems have ushered in a new age of robotics in which once-futuristic visions have either become realities or are on the horizon.  With these advances, much smaller manufacturers can afford to purchase, operate and maintain robotic systems on an annual basis.  There has also been much greater simplicity structured into the operation of robotic systems allowing use by operators with minimal experience.  The advent of the “teach pendant” has allowed programming without knowing how to “code” the microprocessor that drives the process.

 Without the proper precautions in place, robotic systems experiencing a fault or failure might causes serious injuries to people and damage capital equipment in or around the work cell.  Investigations in Japan indicate that more than 50% of working accidents with robots can be attributed to faults in the electronic circuits of the control system.  In the same investigations, “human error” was responsible for less than 20%. The logical conclusion of this finding is that hazards which are caused by system faults cannot be avoided by behavioral measures taken by human beings. Designers and operators therefore need to provide and implement appropriate technical safety measures.

Why can robotic systems be hazardous?  Let’s take a look.

  • Movements and sequences of movements are, at times, almost impossible to follow.   The robot’s high-speed movements within its radius of action often overlap with those of other machines and equipment.  It is not uncommon at all to have several robots operating at the same time and sequenced so that “near-misses” seem to occur.  This is THE reason operational personnel MUST be trained in all operations within a work cell.
  • Release of energy caused by flying parts or beams of energy such as those emitted by lasers or by water jets. 
  • Free programmability in terms of direction and speed.  Speed control is one valuable feature of any robotic system.  Obviously, the faster the movement, the more productivity results.  It is advantageous for the system to travel as quickly as possible providing maximum quality.
  • Susceptibility to influence by external errors (e.g., electromagnetic compatibility) and certainly human factors. Factors external to the system can, at times, affect the operation of the system.  These unknown factors must be discovered, if possible, prior to the system becoming operational.  This involves testing in a very through fashion before putting the system or work cell into production.

To address the increasing sophistication, complexity and needs of robotic systems, stake-holders in the robotics and automation industries are working to establish new international safety standards through the International Organization for Standardization (ISO) for robots and robot systems integration. ISO10218-1, the initial updated standard, published in 2006, specifies requirements and provides guidance for the assurance of safety in design and construction of the robot itself, not the entire robot system.  Part 2 of ISO10218-2 was published in 2011 and covers the integration and installation of robotic systems or cells, thereby providing a more comprehensive set of requirements for robot safety.  I have designed work cells using robotic systems and definitely recommend the following safety measures be observed at all times:

  • The work cell must be laid out in a fashion that allows access to all components and assemblies required to “function” the system.  This means front, back, sides, walls and any overhead space needed for ventilation and access.  With this being the case, it is mandatory the design engineer know the travel characteristics of the robotic structure itself.  Visualize the work cell as a cube and do the equipment layout in that fashion.
  • Always provide voltage to the robot with a switch completely accessible to the operator AND in sight of the operator.  The switch is considered an integral part of the work cell.  Label the electrical enclosure with voltage and phase.
  • Over-amperage protection, i.e. fusing, must be recommended by the manufacturer of the system and adequate to handle all operational situations.  I definitely recommend power to the robot be exclusive to the robot.  Label the breakers with voltage and amperage.
  • Make sure the electrical layout segregates lights, ventilation hoods, fans, etc from the robotic system itself.  When working on the robot, you don’t want the lights and fans on the same electrical switch and enclosure.  You need to see what you are doing with performing maintenance or making necessary repairs.
  • ONLY TRAINED PERSONNEL CAN OPERATE THE ROBOTIC SYSTEM WORK CELL. No one else.
  • Always make sure PPE is used by personnel if necessary during operation of the system.  I would DEMAND safety glasses be used at all times with operating the system.
  • Robotic systems are “dumb” devices absolutely dependent upon adequate programming.  I have never programmed a robotic system right the first time.  Everything looks good on paper and with that being the case, great caution must be observed when taking the system though its initial cycle phases and testing.  Know the reach dimensions of the arm.  Know where it travels at each point on the program and inform the operator.
  • It is recommended that a light barrier or physical barrier be designed into the system so that inadvertent contact by personnel is impossible.  Tell the operator that at no time should he or she try to bypass ANY safety measure. 
  • Only authorized personnel should attempt to modify the control features of the system.
  • The electrical system should have safeguards that “kick in” during power outages and brownouts.
  • Central processing units (CPUs) driving the system should have battery backup to preserve the program unless the memory is non-volatile.

The following must be prevented during rectification of a breakdown in the production process:

  • Manual or physical access to areas which are hazardous due to automatic movements by the robot or by peripheral equipment
  • Hazards which arise from faulty behavior on the part of the system or from inadmissible command input if persons or parts of the body are in the area exposed to hazardous movements
  • Hazardous movements or conditions initiated by the movement or removal of production material or waste products
  • Injuries caused by peripheral equipment
  • Movements that have to be carried out with the safety guard(s) for normal operation removed, to be carried out only within the operational scope and speed, and only as long as instructed. Additionally, no person(s) or parts of the body may be present in the area at risk.

Troubleshooting often requires starting the robot machine while it is in a potentially hazardous condition, and special safe work procedures such as the following should be implemented:

  • Access to areas which are hazardous as a result of automatic movements must be prevented.
  • The starting up of a drive unit as a result of a faulty command or false command input must be prevented.
  • In handling a defective part, all movements on the part of the robot must be prevented.
  • Injuries caused by machine parts which are ejected or fall off must be prevented.
  • If, during troubleshooting, movements have to be carried out with the safety guard(s) for normal operation removed, such movements may be carried out only within the scope and speed laid down and only as long as instructed. Additionally, no person(s) or parts of the body may be present in the area at risk.
  • Injuries caused by peripheral equipment must be prevented.

GRAPHENE

April 13, 2014


THE MATERIAL:

If you follow my posts you know I enjoy discussing all areas of technology especially new and exciting products, materials, processes, etc.   The material Graphene is certainly one of those.   Graphene is  a two-dimensional physical form of carbon.  Its amazing properties include being the lightest and strongest material, relative to all other carbon-based materials.    Graphene also has the ability to conduct heat and electricity better than just about any other substance, thereby enabling integration into a huge number of exciting applications.  It also conducts electricity better than copper and is 200 times stronger than steel but six times lighter.  It is almost perfectly transparent and only absorbs two percent (2%) light.  It is impermeable to gases, even those as light as hydrogen or helium, and, if that were not enough, chemical components can be added to its surface to alter its properties.  Graphene is one form — an allotrope — of carbon, the basis of all life on earth. More familiar carbon allotropes include diamonds and graphite. What makes it unique is its thinness — at one atom thick it is as good as two-dimensional. Its flexibility means that it could potentially be used for flexible or wearable devices.  The carbon represents a single layer of carbon that is bonded together in a repeating pattern of hexagons. Graphene is one million times thinner than paper; so thin that it is actually considered two dimensional. A digital photograph of the lattice-structure is given as follows:

LATTACE STRUCTURE

DISCOVERY:

About ten years ago, the Dutch-British physicist Andre Geim stumbled across a substance that would revolutionize the way we understand matter and win him and his colleague Kostya Novoselow the 2010 Nobel Prize for Physics.  That material was graphene — a one atom thin substance.  According to Dr. Geim;   “It’s the thinnest material you can get — it’s only one atom thick. A tiny amount can cover a huge area, so one gram could cover a whole football pitch. It’s the strongest material we are aware of because you can’t slice it any further. Of course, we know that atoms can be divided into elementary particles, but you can’t get any material that is thinner than one atom, or it wouldn’t count as a material anymore”.

 

APPLICATIONS:

Because of its range of extraordinary properties, people are considering using graphene in a myriad of different applications. For example, because graphene is so strong, people want to use it to reinforce plastics, making them conductive at the same time. People are also considering using it to go beyond silicon technology and make our integrated circuits even denser and speedier. Those are just a few examples.   Typically it takes 40 years for a new material to move from an academic lab into a consumer product, but within less than ten years graphene has jumped from a laboratory environment to an industrial lab and now there are pilot products all over the world. Governments and probably more than 100 companies are spending billions on researching these materials.  So, it probably deserves the superlative of being the fastest developing material we know today.

Other applications include:

Solar cells: Solar cells rely on semiconductors to absorb sunlight. Semiconductors are made of an element like silicon and have two layers of electrons. At one layer, the electrons are calm and stay by the semiconductor’s side. At the other layer, the electrons can move about freely, forming a flow of electricity. Solar cells work by transferring the energy from light particles to the calm electrons, which become excited and jump to the free-flowing layer, creating more electricity. Graphene’s layers of electrons actually overlap, meaning less light energy is needed to get the electrons to jump between layers. In the future, that property could give rise to very efficient solar cells. Using graphene would also allow cells that are hundreds of thousands of times thinner and lighter than those that rely on silicon.

Transistors: Computer chips rely on billions of transistors to control the flow of electricity in their circuits. Research has mostly focused on making chips more powerful by packing in more transistors, and graphene could certainly give rise to the thinnest transistors yet. But transistors can also be made more powerful by speeding the flow of electrons — the particles that make up electricity. As science approaches the limit for how small transistors can be, graphene could push the limit back by both moving electrons faster and reducing their size to a few atoms or less.

Transparent screens: Devices such as plasma TVs and phones are commonly coated with a material called indium tin oxide. Manufacturers are actively seeking alternatives that could cut costs and provide better conductivity, flexibility and transparency. Graphene is an emerging option. It is non-reflective and appears very transparent. Its conductivity also qualifies it as a coating to create touch-screen devices. Because graphene is both strong and thin, it can bend without breaking, making it a good match for the bendable electronics that will soon hit the market.

Graphene could also have applications for camera sensorsDNA sequencinggas sensingmaterial strengtheningwater desalination and beyond.

The published paper fromGeim and Novoselov’s was wildly interesting to other scientists because of graphene’s  strange physical properties.  Electrons move through the material incredibly fast and begin to exhibit behaviors as if they were massless, mimicking the physics that governs particles at super small scales.

According to their article published in Scientific American,  “That kind of interaction inside a solid, so far as anyone knows, is unique to graphene,” wrote Geim and another famous graphene researcher, Philip Kim, in a 2008 Scientific American article. “Thanks to this novel material from a pencil, relativistic quantum mechanics is no longer confined to cosmology or high-energy physics; it has now entered the laboratory.”

DRAWBACKS:

Every new technology is somewhat evolutionary instead of revolutionary.  For this reason, obstacles will need to be overcome for mass production and use.

The material is still in an infantile stage compared to developed materials like silicon and ITO. In order for it to be widely adopted, it will need to be produceable in large quantities at costs equal to or lower than existing materials. Emerging roll-to-roll, vapor deposit and other production techniques hint that this is possible, but they’re not yet ready to bring graphene to every mobile device screen out there. Researchers will also need to continue to work at improving  graphene’s transparency and conductivity in its commercial form.

PRODUCTION

While graphene shows promise for transistors, it has a major problem: It can’t switch the flow of electricity “off” like materials such as silicon, which means the electricity will flow constantly. That means graphene can’t serve as a transistor on its own. Researchers are now exploring ways to adjust it and combine it with other materials to overcome this limitation. One technique involves placing a layer of boron nitride–another one-atom-thick material–between two layers of graphene. The resulting transistor can be switched on and off, but the electrons’ speed is slowed somewhat. Another technique involves introducing impurities into graphene.

Graphene may also be emerging too late for many of its possible applications. Electric car batteries and carbon fiber could be made with graphene, but they already rely on activated carbon and graphite, respectively — two very inexpensive materials. Graphene will remain more expensive for the time being, and may never be inexpensive enough to convince manufacturers to switch.

The world is only a decade into exploring what it can do with graphene. In contrast, silicon has been around for nearly 200 years. At the pace research is moving, we could know very soon if graphene will become ubiquitous or just another step in discovering the next wonder material.

I welcome your comments.

 

 

FOR WANT OF A NAIL

April 12, 2014


“For want of a nail the shoe was lost; for want of a shoe the horse was lost; for want of a horse the rider was lost.”

I have no idea as to who first said this.  His or her name has been lost in time, but if you apply this anonomous saying to modern-day events, you would have to deduce that General Motors (GM) should have known better than substitute a less expensive ignition switch for one much more robust.   One that could take punishments known to exist over the life of an automobile.     Ignition switches used on cars today not only supply voltage to the starter but enable the air bag and other devices critical to smooth and continued operation.  These devices are certainly in the safety circuit and MUST fail safe when and if failures do occur.  THEY ARE CRITICAL TO QUALITY.   Critical to quality is a term used frequently in design, manufacturing and quality control to designate components that insure safe operation and performance of an electo-mechanical device or an assembly of devices.

During any component design phase, limits of acceptability are established.  These limits represent the maximum/minimum parameters defining the range of operation.  These limits “bracket” acceptable performance for all possible uses or misuses of the equipment or component.  Good quality programs monitor manufacturing and operational trends relative to the limits of acceptability so mid-course corrections during the manufacturing phase may be made.  This insures continued acceptable performance for the product.

An ideal component or assembly of components would exhibit six sigma (6 σ) levels or no more than 3.4 component defects per one million parts or assemblies produced.   This is the goal of every manufacturer—to achieve six sigma levels thereby improving manufacturing thru-put yield of component parts.  This can be very difficult in today’s world due to economic pressures and competition.  In the United States today, the average “sigma” value approaches four.

Component and system reliability is measured by Mean Time to Failure (MTTF) and Mean Time Between Failures (MTBF).  These times are established by reliability testing or cycle testing under varying conditions.  Cycle testing is usually performed by HALT (Highly Accelerated Life Testing) or HASS (Highly Accelerated Stress Testing).  Time to failure results from these performance tests.  MTBF determines maintenance times for the components and/or assemblies.  Understanding of this time frame is critical and determine preventative maintenance or replacement schedules.   Please note, evaluation laboratory testing and reliability testing  are two distinct methodologies to determine acceptability of a component or subassembly of components.  Both efforts are absolutely necessary and provide valuable information relative to manufactured parts.

One excellent predictive tool is FMEA (Failure Mode Effect Analysis).  This is a methodology used to discover probability of failure, severity of failure and frequency of failure for all possible failure modes.  Quantative estimates are given to each possibility thereby producing a conglomerate number that designates acceptable performance, marginable performance or unacceptable performance relative to failure type.  Generally, numerical values are derived by multiply the three estimates together.   An unacceptable value requires engineering to re-think the design thus eliminating the failure mode or providing for early detection of that failure mode.

I would hazard a guess that any ignition switch used by GM would have undergone similar investigations by virtue of testing.  These guys are not dummies and if that is the case, what happened?  I would surmise cost factors and margin played a significant role in the acceptance of these components.  At any rate, GM will have to account for the failures.  Thirteen (13) people were killed due to switch failure.  We are told the cost to rectify this problem would have been less than one dollar.  GM will not escape the repercussions—they know better.

I welcome your comments.

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