Among the mainstays of an industrial economy is construction, housing and commercial in particular.  While these industries are incredibly competitive, there is always room for innovation.  Precisely because it is a mature, competitive industry, really ground breaking solutions are sometime hard to find.

Transcon Steel is a small startup company in Georgetown Texas that makes structural steel building systems.  The innovation comes from the fact that Transcon roll forms flat sheet metal into structural shapes that are highly optimized to reduce weight and increase strength.  The steel structural shapes are formed into large panels with compressed foam which results in structures that are super light weight and extremely high strength.

The new structural panels permit construction of buildings in a variety of applications.  So called “temporary housing” for oilfield crews in remote area can be built in hours instead of days.  Heating and cooling costs are a fraction of conventional structures.  All of which leads to increased opportunities to serve unique construction applications with better solutions.

Transcon’s big challenge will be to create the manufacturing resources needed to produce the structural panels in very large numbers.  The enabling technology of the manufacturing processes?  Mechatronics. The roll forming of sheet metal is a classic application requiring high performance drives to de-reel the strip steel rolls and servo actuators to follow the roll throughout the various forming process that take place to make the final product.

The compressed foam requires unique tooling to form large rectangular panels that can be filled with foam, compressed with hydraulic actuators and cured with heat and pressure to form the final super dense structures.  Amazingly, the cores are made from material that is similar to the conventional styrofoam cups we use for coffee, yet, when the basic material is processed correctly, it becomes strong enough to withstand blows from a sledgehammer.  When it is bonded to an already strong steel frame, you have a complete building system that has incredible structural strength and insulation value.

Transon is negotiating enough new business that it will need a new facility 4 times the size of it’s present location and will hire CAD designers and plant personnel to support it’s manufacturing needs.  If they are successful at marketing the technology in other countries, it will be more of the same.  Lots of it.

And that is how job creation is done.  Someone with an idea, willing to work hard, taking risks, finding people to come alongside and help, to deliver a solution.  Making lives better by employing people, and by delivering a product that provides shelter at a lower cost than the traditional products in the building market.

American Entrepreneurship.

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A lot of it is precisely ‘doing more with less’.  How do we make the same quality of parts at prices low enough to compete with foreign competition?  It’s not easy when the typical pay scale for manufacturing labor is $8 a day in some parts of the world.

There are a couple of obvious components to price competition that don’t get a lot of attention.  Scrap rates and delivered cost.  When a US company buys parts from offshore, any defective parts are very costly.  The direct shipping cost, duties and processing fees are additional and can be 10-15%.

During my years at Rockwell Automation, we investigated the cost of selling US products in different parts of the world.  Depending on where in the world we are talking about, the shipping and logistics can accumulate between 25 and 40% additional cost to the product being sold.

So the cost of scraps and logistics are the minimum cost hurdles for companies seeking to export their products to the US.  Low cost producers have to make parts cheaply enough that the landed cost and scrap rates cost out less than the price of producing them in the US.

Doing more manufacturing in the US requires finding creative ways to lower costs.  That is the second area that is undergoing change.  American manufacturing technology is finding ways to reduce machinery and process costs.  And this area of effort may provide key strategies that will help the US gain back ground in the pursuit of more world class manufacturing.

Innovation processes like additive manufacturing allow fabrication of metal parts with no machining.  For higher levels of precision there are new machine tools that can do final machining to less than 0.001″ accuracy and the costs of machine tools are lower than ever.  These are the keys to producing high quality parts at lower costs.

There are unique mechatronic solutions that can improve machinery performance across a wide range of applications.  The Acme screw which is very inexpensive, has limited accuracy but plenty of torque handling capability.  What happens if you can add a very inexpensive linear feedback technology to the simple low cost Acme screw?  You get a really high resolution linear motion system that is very inexpensive.

The great news is that these products are currently available.  And that means that making better machines that make better parts at lower cost is practical, achievable and there are no technical challenges.  Common off the shelf parts will get it done.

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The electric light, for example, which was coveted 100 years ago as the great solution to night time darkness, making obsolete the candle or gas lamp.  Mass production has made the light bulb an inexpensive  commodity on the verge of extinction at about 25 cents per bulb.  The desire to reduce energy consumption is ushering in the age of the light emitting diode (LED) as the replacement technology for electric light.  Every effort is under way to reduce LED costs by any means possible so that illumination will be available that is even cheaper than incandescent lighting when the energy cost over ten years is factored into the new technology.

Even generating and delivering electricity is the result of applying the principles of mass production.  Large generating facilities are able to generate power cost effectively through economy of scale, selling the power profitably at 4.5 cents per kilowatt hour.  Wire, cable, switching systems and other infrastructure are generally costed in at an additional 2 cents per kilowatt hour to deliver the power to your door.  This is an incredible deal, trillion of dollars of resources at your disposal for pennies.

But mass production is not the answer for every aspect of modern society.  Lowering the cost of mass-produced goods implies that there is a requirement for the sufficient numbers of a product to warrant the investment in the necessary processes and tooling to accomplish the task.

Enter 3D printing technology.  Also known as “Maker bots”, this new class of tools is making fabrication a  new American pastime at incredibly low cost.  Where 3D printing equipment has recently been the domain of well-funded large corporations , selling at $10,000 to $20,000 each, 3D printer kits are available at less than $1000.  And lest you think that these are only toys for boys, the additive manufacturing paradigm has taken hold in the metals industry producing high quality parts in various steel alloys and even in titanium.

Why does it matter?  Because anything that lowers the barrier to market entry for new products creates the opportunity for people to enter a market that was previously inaccessible.  The hidden relationship is financial, it is the cost of amortizing the manufacturing resources across a given number of products that makes startup of a new product impractical.  So barriers to entry in new product development are primarily the result of amortization costs.

What happens when a new technology introduces a significant reduction in the amortization cost?  You get the opportunity to experiment with things because the cost of iterating the design is low.  New products can be test marketed and improvements made because there is no major investment in tooling that would have to be modified in order to change the design.  You don’t have to get it right the first time.

And that means that anything is possible.

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The traditional metal cutting machine tool has been around since the 1800′s and was entirely manually operated.  Since the machines were manually operated, the dexterity of the operator became a major factor in accuracy and repeatability of part manufacturing.  Because of the skill required, we still have the term “master machinist” in circulation, even though most machining today is automated.

During the Second World War, the Air Force was confronting the difficulty of manufacturing airplane parts.  Through the work of John Parsons and MIT, the first “punch card” controlled machine tool was built.  Parsons’ company was using early punch card computers to generate a larger number of points along the curve of a wing brace.  The numerical information was then used directly by machinists as a look up table for manually positioning a milling tool.  Parsons realized that if they could motorized the manual process, it could greatly increase the speed of the machining process, lowering costs dramatically and increasing accuracy at the same time.

Gordon Brown’s Servomechanisms group at MIT has recently been working on early forms of closed loop dc motor control for the gun turret on B-29 bombers.  By combining these recent technologies to numerical punch card calculation approach the first Computer Numerical Controlled Machine Tool was demonstrated.

The rest, as they say, is history.  The lessons learned in computer numerical control have been instrumental in every major field of manufacturing.  Cars, electronics, robotics, would not be feasible or cost effective without the underlying control technology of CNC.

Which brings me to a 2 major points as we contemplate the next generation of manufacturing.

Additive manufacturing is maturing rapidly with a wide range of materials, steels and titanium are now available, and precision is improving at the same time.   The surface finish requirements for a large number of parts cannot be achieved with a strictly additive process.  The new wave of additive manufacturing requires a complementary subtractive technology at complementary prices.

Secondly, while there are an increasing number of machine tools at low cost, they are not CNC.  This will likely be the next “breakout” technology.  There are a number of technical hurdles that have to be addressed in terms of reducing the cost to a level comparable with the Makerbot.  With the current generation of dedicated motion controller chips, lower cost step motors and low cost feedback technology, this should be a slam dunk.

Get your pencils out and get after it!  There’s some serious money to be made here.

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Alternative energy in the US has failed to produce the return on investment or to create new jobs in any significant numbers.  Car sales have picked up significantly over 2011, but not nearly at the rate of 16 million cars/year as in the heyday of that industry.  The real estate bubble has burst after a decade of speculation and bad lending practices that continue to depress new construction.

The second industrial revolution, Henry Ford’s industrial revolution, was about mass production and cost reduction.  For almost 100 years we have been perfecting the centralized manufacture of almost everything around us.  Economies of scale that enable volume manufacturing of consumer electronics at lower cost year after year are the result of the Ford approach to manufacturing.

So where do we go from here?  We start re-inventing the industrial revolution.

The new wave of manufacturing has begun with the advent of the Maker Bot and a family of low-cost fabrication tools that can manufacture based on 3D printing techniques.  While solid model prototyping has been around for some time, the magic ingredient is a new family of machines that cost less than $2000. and some recent new entries around the $1000 mark.  At these price points, it doesn’t take a lot of volume to justify the purchase of one of these machines.

There are advanced processes that are becoming available to generate sintered metal parts, even titanium parts, using processes resembling the additive manufacturing process.

Amortization cost is the secret.  Lowering amortization costs and minimum order quantity at the same time results in a fantastic breakthrough in productivity.  It also lowers the barrier to entry into new markets.  So if you have an idea for something that’s never been done before, the cost for development may be a lot lower than you think.  And thousands of people have begun to jump into the mainstream economy because of the availability of these new tools.

While the “maker” tools are limited to plastics, there is progress in the metals arena as well.  The computer numerically controlled (CNC) machine tools have traditionally been the domain of 6 figure costs, HAAS has been making $50,000 machines and last year Tormach entered the market with the “Personal CNC”, a high quality machine that is priced at $10,000.

My prediction?  There is going to be a lot of activity at the $10,000 and below price point to come up with low cost machine tools as a complement to the “maker” bot 3D printer technology.  Additive manufacturing will require a complementary subtractive manufacturing infrastructure at a comparable price point.

And creative American engineers and tinkerers will be leading the way.

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In the wind energy arena the biggest change has been the shift to direct drive permanent magnet generators.  By eliminating the gear “increaser” to convert the low RPM of the propeller system to a high RPM for a standard high power generator.  This is crucial step in bringing the cost of wind power down. Current systems are weighing in at 100 tons and have to be suspended above water or land 165 feet in order to pick up sufficient wind currents to be economically practical.

There is no single solution that is ideal for wind applications.  One supplier has a generator that is made up of 4 smaller units on a single large ring gear.  This system seems to have significant advantages in reducing the size and weight of the generator and makes maintenance more simple in the event of a failure.

Among the major mechatronic challenges driving change in the motor industry, electric vehicle applications are continually pushing the boundary for energy density and efficiency.  The performance demands of electric vehicles and other mobility applications make every percentage point of efficiency crucial to the range of the target vehicle.  This has led to a rash of new motor and drivetrain designs with a variety performance capabilities.

Each new innovation seeks to organize the basic materials of the electric motor in a new way to improve some aspect of performance.  Electric motors are copper conductors, “soft” magnetic steels and many times, permanent magnets.  The basic costs for copper wire at $5-6 a pound, commodity strip steel is about $.50 per pound but has to be punched in precise shapes, coated with insulation and stacked into larger assemblies, and $16. per pound for permanent magnets.  Complex processes associated with motor manufacturing make motor costs considerable.

In a recent development teams in academia in Australia and the US have developed simple low RPM motor structures based on polymer actuators referred to as “artificial muscle”.  While this development is in its early phases, the simplicity and low cost are significant and very appealing.  A demonstration of the new technology can be seen on YouTube at;  www.youtube.com/watch?v=ZcCPNJR5PCMand it is very much worth the watch.

The only sure thing is that we continue to meet the challenge of new market needs with innovation.

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Many of the constraints of the work are environmental.  If work is being done outdoors, then temperature and humidity are a factor.  Felling trees and in the forest requires extremely high forces due to the work needed to cut through a tree and drag it to a truck to be hauled off for processing.  Processing trees, even in a plant environment, requires some serious hardware, 125 horsepower band saws are not unusual.

Doing work on a ship or oil rig has additional constraints because of the presence of explosive fumes and fuels.  Often the need to avoid any possibility of igniting a combustible atmosphere causes engineers to apply pneumatic control systems.  Yes, there is still a compressor somewhere to generate the compressed air supply, but that is usually remote or contained to avoid exposure to the volatile atmosphere.

Environmental constraints come in many forms.  Extremely high temperatures push the limits of what is possible.  Making glass, semiconductors, and primary metal processing are all high temperature environments where engineers have developed whole technologies in order to bring us the materials we use in everyday life.

The simplest action of rolling or sliding becomes a real challenge when environmental constraints are added to the work statement.  Sawdust becomes a potential abrasive in woodworking environments that can introduce severe wear in moving parts.  Corrosive and explosion proof atmospheres as well as food industry applications introduce all sorts of chemical compatibility problems that require special materials and processes in order to meet strict guidelines for safety.

As always, resourceful engineers have worked out solutions for all of these difficult applications.  One family of solutions to rolling applications is the use of all ceramic bearings.  No steel, no lubrication.  None is needed because the ceramics are extremely high purity to start with and have extremely high precision surfaces eliminating the need for lubrication.  No outgassing or contamination to worry about.

Other solutions take the form of air bearings and non-contact material handling devices.  Air bearings have become more readily available for conventional applications, but are particularly compelling in large machinery applications where precision is required.  Large flat screen display glass  presents unique challenges that successfully addressed using a combination of air bearing regions and vacuum regions to move the glass without actual contact and with overall flatness measured in millionths of an inch.

A unique solution in pneumatic material handling takes compressed air driven into a funnel shaped recess and creates a vacuum in the center and an air cushion at the edges where the air is exiting.  This creates a vacuum pickup that never quite comes in contact with the part, leaving no marks.  Perfect for solar cell and some food and beverage applications.

Engineers continue to meet the unique challenges of industry and create commerce at the same time.  And that’s what it should be about.

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Start with the big loads.  Plant air handling, building HVAC and lighting are generally a lot more significant in total Watts or equivalent horsepower.  1 Horsepower is equal to 746 Watts.  If you are located in the northern states, winter heating uses a lot more energy than summer air conditioning.  In the southern states, it’s the opposite.  There is one study that puts the northern thermal cycle at a much higher overall cost, so everybody needs to move their manufacturing to the south.

Check all the integral horsepower motors in the plant.  A recent DOE study shows that over time, many motors get replaced with whatever is readily available in the next larger frame size.  This is in reaction to plant failures where the exact replacement motor is not handy or on the shelf.  The result is that the plant power and power factor can be very poor because there is a lot of excess capacity that is not being used efficiently.

Industrial plants also suffer from peak demand billing practices.  The utility company agrees to provide power, but large users get billed extra when they have peaks above their average usage.  Again, look at the large loads, and see if some or all can be put on soft starters or inverters with longer starting profiles.  AC motors try to get to full running speed and spend several seconds at poor power factor and huge inrush currents during starting.  Most motors require at least 4 seconds to get to speed.  So, is there a savings opportunity if you can get by with a 6 to 10 second starting period?  Yes, there absolutely is.

The smaller loads like individual plant floor machines are a little harder to regulate.  Some production machines consist of dozens of individual motors and sub-systems.  In large conveyor installations, newer control system turns off whole zones of equipment if there is no traffic for that section.  Use the same strategy in production equipment.  If there is nothing coming into the machine, turn off as much stuff as possible.

Again, look for the largest loads.  In CNC machines, the spindle is usually the dominant load.  Turning off a 10kW spindle motor will save lots more money than turning off 400 Watt positioning axes.  However, don’t pass up an opportunity if one exists.  If there are a large number of individual axes of motion that have low duty cycles, it may be cost effective to put brakes on the load and turn the motors off when they are not in use.

Prudent planning can be turned into real cash savings.

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This is rather ironic considering the billions of dollars that are spent on control systems across all fields. Is control fundamentally any different if it is inside a car, automating lighting and HVAC in a large building, on an automotive manufacturing plant floor, in a biological resesearch laboratory, or in a giant refinery where chemical products are made.  It’s all control.  And the more we try to define it, the more inclusive we make the definition, the more vague and ambiguous the term becomes.

Efforts continue to increase the power of the PLC (programmable logic controller) across many vendors. By increasing processor speed, memory and capability PLC’s are becoming the universal platform of control as a discrete controller, process controller and motion controller.

Simultaneously, motion control specialty companies continue to increase speed, processing power and I/O structures in an effort to expand the dedicated motion controller as a competitive platform to the PLC.  This is a necessary migration to address control applications where an external PLC could be eliminated.

Is there an ideal mix of motion axes and I/O that will help resolve which hardware solution is best?  Not really.  The fact is that the majority of the market is made up of motion control using stand-alone axes that are triggered by logical conditions in the system.  Coordinated axes require the sharing of pulse to pulse position feedback information.  Stand-alone axes do not share data at that low a level in time.  Most PLC controllers are well able to handle stand-alone axes, especially if an intelligent indexer is used.  This off-loads the motion to the servoamplifier and only I/O handshakes are used.

Part of the ambiguity here is that control is the result of hardware and software together.  ’Control’ seeks to generate complex behaviors using digital methods.  The digital methods, processors, depend on programming techniques in order to implement the desired behavior.  So when we talk about Control, we are talking about hardware and software simultaneously.

What matters most to users of automation technology is both logic control and motion control programming exist in a single environment.  It doesn’t matter if the programming environment is a PLC with motion blocks inside it, or a motion controller with logic blocks inside it.  What matters is that all aspects of a control system can be programmed using a single editor.  Controllers from the major electrical companies like Rockwell Automation and others have opted for the logic-centric programming environment with motion blocks in the ladder diagram.

This approach eliminates the complexity of multi-processor solutions, each with their own programming language, that were commonplace a few years ago.  Multiprocessors have their own unique programming environments and a significant amount of programming to create proper interaction between the various platforms.

Missing from this description is the hard wired control that is part of system start up, power management and safety.  More on this in the next installment.

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Government is not the answer.  Anytime government gets involved there is a very high risk that money will get spent and nothing will change.  Remember stimulus 1?  We were assured that if this money were spent, unemployment would never go above 8%.  And with unemployment at 9.1%, the administration wants to try stimulus 2.  No thanks.

What are the real unemployment numbers?  No one wants to really talk about that because it would mean having to admit that the real number is much higher.  Quoting from the most recent data provided by the Bureau of Labor Statistics (BLS), there are 14 million people unemployed, officially, with a labor force that has increased to 153.6 million in August.  That’s where the 9.1% comes from.

But the BLS also reports 2.6 million people “marginally attached to the labor force”.  This category refers to people who have been out of work over the last 12 months, ready and available for work, but had not looked for a job over the last 4 weeks.  I’m still not sure I understand this categorization, certainly someone who has been out of work for 12 months should qualify as unemployed.  The quibbling over details here is clearly designed to hide the real numbers.

2.6 million plus 14 million is 16.6 million which is 10.8% unemployment.  The psychologically dreaded 10% unemployment number could be easily avoided if one can find a way to finesse the reporting categories.   How bad is it really?  Some commentators have said the real unemployment numbers are 16% or higher.  Donald Trump said it was 20%+ in his interview with Greta van Sustern last week.  Personally, I am quite sure its something above 10.8%.

Sadly, this is not the first time employment data has been misrepresented.  Remember how the “Green Economy” would generate 30,000 jobs?  The report that was quoted by many in Colorado State and Federal government used a number of statistical machinations to “fluff up” the numbers.  Workers who put insulation in your home were counted as part of the “Green Economy” as were a fraction of the appliance manufacturers workforce, since effort to reduce energy consumption is a part of that industry.

Attempts by government to increase employment have been mediocre.  The way government creates jobs is by adding more government workers.  Which this administration did like crazy in its first year.  This is not how we grow the economy.  Every dollar spent by government is at the expense of someone who works for a living.    It robs the consumer of discretionary dollars that can be spent in the real economy.  When things get bad enough, government spending robs people of their ability to pay for necessities.  This isn’t how it’s supposed to work.

More disturbing is the trend in the number of manufacturing jobs added per month.  The manufacturing sector added 14,000 job per month in the second quarter, compared to 35,000 jobs per month added in the first quarter.  Not a good trend.

There are two big lessons here.  One is that manufacturing is where the jobs are. American jobs and American manufacturing.  Our politicians have been running down the manufacturing sector for the last 20 years.  Second is that government is not the answer.  Americans and American ingenuity are.  So let’s agree to let American’s get about the business of inventing the future and get the roadblocks out of the way.

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Cooking raw sugar and turning it into white sugar, for example, requires incredible amounts of heat and steam.  And generating steam requires a lot of energy.  Steam is very expensive to generate and almost impossible to store.  The cost of steam is so high that plants measure steam loss by the second.

Producing magnesium as a metal is a large scale electrolytic process.  The emphasis is on electrolytic.  The plant I visited measured current in 10′s of thousands of amperes.  There was so much power that the PC screens in the building had to be triple shielded or the magnetic field of the power distribution system would mess with the displays.  Huge annual cost of energy.

Where industry and commerce require significant amounts of energy to operate, these businesses become very sensitive to the cost of energy.  The same is true for individuals.  As the cost of gasoline increases we must individually choose to use less, or since some people don’t have the option to use less, pay more for gasoline and have less income to spend on other things.

Energy policy under the direction of the DOE and Congress has promoted solar power and wind power over coal, natural gas and nuclear energy.  There are two problems with this approach.  First, these technologies are very expensive.  Any time someone promotes technology and won’t talk about cost, you should be suspicious.  And that has been the history of alternative energy.

The second problem is that there is currently no way to store the power that is generated.  So unless you can use the power immediately, you’re in trouble.  A popular solar project is cited that used solar panels to generate peak power during the summer afternoons during periods of increased power demand when high air conditioning loads are required.  This is still a very expensive solution, but where the utility charges 3 or 4 times more for electricity during peak demand periods, this solution makes sense.  But it is a very limited application.

The question is, who decides how much energy will cost in the US?  State governments grant permits to open a utility.  They also decide what the utility companies’ goals will be.  The DOE has created consensus about alternative energy without approval from Congress.

Do the decisions of the government make sense?  That’s where the controversy starts.  If you are trying to run a business, then anything that increases costs is probably bad.  But no one in government appears to be listening.

Many businesses and almost every consumer is impacted by the decisions made by government.  Every extra dollar that is spent on lighting,  heating and cooling, and transportation is a dollar that is no longer discretionary.  So maybe that’s the real question.  Who decides what you and I spend our money on?

To the extent that government Policy causes dollars to be paid as increased energy expense, then the rest of the consumer economy suffers.  Which is part of the current problems that our economy is currently experiencing.

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Semiconductor costs decrease over time as volume increases.  This has been the magic of the industry for decades.  The cellphone, flat screen monitor, tablet computer all represent incredibly low cost of technology as a result of massive volume production.  All of these technologies had incredibly high investment cost.  A typical wafer fab was in excess of 3 billion dollars last time I checked the price.

Lots of different chip technologies have followed the extraordinary shift in pricing as the specific technology matures.  Power semiconductors continue to increase their power handling capability at decreasing costs.  This has been a great advantage for the motor and control industry.  Processor technology that is motor specific has undergone similar cost performance improvement.  Digital signal processors used to be the primary choice for motor control.  DSP’s have been replaced by a number of other technology options, dedicated microcontrollers and FPGA’s being the most cost effective.

What is really startling is that not only has the cost of the chip technology fallen, but the development tools to create new applications has fallen as well.  If you can afford the price of a PC, development software like LabView, you can define a completely new application, program and download executable code in a target processor.  Voila!  Working application!

If your target market is 5oo units of some cool new product, and you can put the development system together for less that $5000., then a $10 amortization is all that is required in the first year to reimburse you for the investment in a development system.  Combine this with $1500 3D printer that can make solid parts and the possibilities are endless.  If you need metal parts, use the 3D printer to make prototypes that can be used for metal casting models.  Even the metal casting industry has learned to decrease it’s volume requirements to gain access to lower volume market requirements.

Economies of scale have been a powerful agent of change in the age of electronics.  But by themselves, economies of scale are not sufficient to create a major change in the dynamics of entering new markets and creating new industries.  The cost to design, program and implement a technology has to be considered as part of the overall economics of new technology.  The latest innovations in development of technology are dramatically addressing the cost of development.

Lower development costs mean lower cost per unit for whatever new product is being considered.  The new revolution in manufacturing will be ongoing developments that change the way new products are designed and brought to market.

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The cost of control is extremely important in terms of its impact on what is “practical” in the world of production.  Even in medical, military and aerospace systems where cost is often a secondary consideration, the actual cost and performance of a new process or piece of equipment has to be gauged against the benefit that it will produce.  If the benefit is greater in value than the cost, then funds and effort need to be committed to the new project.

There are significant trends in the marketplace that are constantly changing the cost of control.  As we look at the mechatronic arena in particular, recent increasing cost trends for copper wire, lamination steel and permanent magnets have been pushing prices up steadily in the range of 5-6% per year.  This situation is expected to continue.

Recent threats from China about restricting export levels for Neodymium magnets have made magnet pricing very speculative, read high as a kite.  However, Molycorp and others around the world are bringing Neodymium ore into the market and companies like Arnold Magnetics are gearing up to provide finished products without the use of Chinese sourced material.  Good new to those in the motor sector.

On the control side of mechatronics, the power Fet has dropped in cost by 50% in recent years and costs are expected to continue to decline following the traditional cost performance over time that is characteristic of the semiconductor industry.  Add to this the incredible cost performance improvement in embedded microcontrollers used in motor control circuits and you have even more good news for the mechatronic suppliers.

Bandwidth for these controllers now provides motor control that operates in the sub-microsecond range with efficient instruction sets and pre-configured PWM macros to make code creation more efficient.  Typical pricing for these processors is well under $5 making them ideal for a wide range of applications in industry and commercial white goods.  The marriage of low cost motor control cores and reduced cost power electronics should signal declining prices for motor controls for the mid- to high performance applications.  This cost improvement should more than offset the price increases expected in the cost of electrically controlled motors.

Some families of processor have native CAN or Ethernet communications interfaces with multi-threading software to guarantee that high priority instructions in the motor control code will not be impacted by messaging from outside applications.  Network technology is providing fast, and in some cases, deterministic forms of Ethernet like EtherCat making the servo network the control architecture.   This approach to the network demands of high performance control reflects a general shift to low cost, high reliability platforms that are ready to transform the controls landscape in the mechatronic arena.

It’s an interesting time to be in the controls business.

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As control technology has progressed over the last few decades, the performance requirements haven’t really changed much in a certain sense.  In the case of Computer Numerical Controls, the basic performance hasn’t really changed.  The big difference has been the cost.  The early CNC at $500,000 has been replaced by today’s production CNC at $50,000.

Certainly, there have been significant advances in capability, larger machine structures for aerospace applications, high precision applications and even the advent of the “maker bot” low end machines.  But the basic relationships required to shape parts in 3 dimensions are the same.

Yes, there are example of industries and applications that simply didn’t exist 50 years ago, like semiconductors, flat panel displays, etc.  Most of the improvements in electronic motor controls and motion control actually derive from the work done to improve the disk drive spindle motor.

But generally speaking, industrial control has migrated from specialized control hardware, to the PLC, a general purpose, high reliability form of controller, to personal computer based solutions.  Primarily due to the low cost and high performance computing power of the PC.

Some of the performance attributes have to do with how a given control is architected.  In the push for high reliability, the PLC goes to great lengths to insure that memory cannot be compromised, input-output hardware is extremely resistant to external electrical interference, and state changes are captured in a rigidly deterministic manner to insure that control code executes consistently.  In the PC there are PLC emulators that have been approved by various agencies that qualify their performance as equal to PLC’s.

Some attributes of performance are not obvious.  The operating system and its performance become part of the control system equation.  If the OS faults, the control system is down.  Hence the advent of Real Time Operating Systems, Linux and a host of other solutions aimed at reliability.

It can go deeper than that.  Exactly how the OS deals with interrupts can mean the difference between reliable operation and catastrophic failure.  Windows CE has different performance attributes over Windows for industrial control application.

In the PC architecture, how does data move from the disk drive to the operating program?  In the PLC how does the backplane impact the update rate of field I/O?

In the software realm, newer operating systems have made possible multi-threading programs that allow several task to execute simultaneously in the same hardware and software environment with complete coordination between tasks.  Robotic and CNC applications with multiple system operating in a single controller are able to execute separate programs with sophisticated anti-collision detection.

So exactly where the control system performance originates from is not exactly a function of a specific piece of hardware, but rather the result of hardware, OS and software combined to achieve a desired outcome.  Not a simple matter.

Mechatronic Tips

A major lesson that I came away with was imparted during one of my attempts to repeat the course with a passing grade. (It took me 3 tries before I passed)  ”Always pay attention to the units of measure when you are trying to analyze a problem”.  In the problem solving arena, trying to figure out the relationships is sometimes a little easier when you just look at the units of measure.

In energy its really important to understand the units of measure.  Electrical power is measured as Watts.  Watts can be used as a measure of electric light, electric heat or any form of energy which can be directly derived from electricity.   As we seek to conserve power it is important to consider how efficient it is to convert electricity to another form of power.

The often ignored unit of measure is time.  It is especially important in energy measurements because the ratings of equipment can vary dramatically between starting conditions and running conditions.  Most motors and heaters have a significant inrush current when they are first switched on and then settle over time.   The ratings need to be examined more closely to get this information.

So a 100 Watt light bulb left on for 10 hours is one kilowatt hour.  The cost of a kilowatt hour varies around the US, but here in Texas its around 11 cents.  A computer with a high resolution video card can use 400 Watts.  In this case we are exploring the “dollars per kilowatt hour” for various appliances.  A large refrigerator can use 500 Watts, which is substantially better than older units with ratings over 1000 Watts.  And a central air conditioner rated at 5 tons can run as high as 17,585 watts or $2.00 an hour when running at full load.

When comparing electric motors, regardless of type, Wattage and duty cycle are consistent units of measure for the power that can be produced by the motors.  In this arena what is really being measured is the amount of work that can be performed within the thermal limitations of the motor and drive.  This is really important to keep in mind because at the end of the day it’s all about the amount of work required and the cost of the solution.  The units of measure might be $/kW or $/inch pound of torque.

When comparing motor and drive hardware from various suppliers, make sure the units of measure are the same (which they usually aren’t) and the thermodynamic basis for the ratings is similar.  The exact size of the cooling plate, what material its made of and how long the motor is run for thermal testing is all part of the rating system.

Some years ago I was confronted with a torque comparison between a 4″ servo from one vendor that claimed to put out the same torque as a 5″ servo from another vendor.  After considerable effort, an associate came up with the real answer.  The smaller servo was rated at a thermal limit 50 degrees higher than the larger one.  Although ratings are generally not so disparate in today’s market, there is still plenty of variation that has to be considered.  So make sure you know the units of measure.

Mechatronic Tips