Efficiency needs a system approach, depends on individual applications

Energy-efficient motion control: To identify the most energy-efficient pneumatic and electric automation, a technology-neutral comparison is required. After considering different alternatives, a German automotive components supplier adopted a ready-to-install energy-efficient handling system.


High rigidity and low moving mass: The pyramid-shaped, enclosed design makes the robot highly dynamic. At the same time, the handling unit is more accessible and allows faster production. Courtesy: FestoWhen consumers look for an energy-saving washing machine, they simply buy the device with the best energy-efficiency rating. For manufacturers of washing machines, things are more difficult. If they want the most energy-efficient production facility, they realize that no certification of energy-efficiency classes is available.

"Energy efficiency in automation is dependent on the industrial application in question," explained Festo energy-efficiency expert Dr. Axel-Andreas Gomeringer.

The only reason it is possible to classify washing machines into energy-efficiency classes is that the usage scenario of a washing machine as a closed system is precisely known. For example, all devices can be compared easily on the basis of their standard cotton program with a 60 C wash temperature. For machinery and installations, however, the system parameters are not clear. Should only the drive be assessed, or the control chain, or the entire factory?

Define tasks clearly

Any industrial application has its specific requirements for technical criteria such as speed, load capacity, power to weight ratio, accuracy, control behavior, rigidity under load, and efficiency or robustness, and also for economic criteria such as the purchase cost (price, commissioning, installation) and operating costs (maintenance, durability, energy costs). In any application, energy efficiency depends on the specific task. "The task must be clearly defined before the user chooses a drive technology—electric, pneumatic, or a combination of the two,” explained Gomeringer, head of innovation and technology management at Festo.

Intelligent dimensioning

With engineering software, users require just a few key data to arrive at the right solution. Which electromechanical linear actuator best meets requirements? All that is needed is the input of position values, payload, and the installation position, and the software will suggest an optimized solution. This eliminates wasted energy by incorrect sizing.

A common dimensioning process for mechanical drive and transmission components and motors prevents a duplication of safety factors, which would result in oversized electric drive systems and a waste of energy. Calculations have shown that, with consistent use of sizing software, energy costs can be reduced by as much as 70%.

Energy savings in the system

Often success stories about energy-optimal solutions really get started with complete handling systems and control technology. Supplied ready-to-install and fully pretested, lightweight handling systems such as a high-speed handling robot can be delivered directly to users’ applications. The low weight of the robot, with its rod kinematics made up of standard electromechanical components and ultralight carbon fiber rods, ensures the efficient use of drive technology. With a gantry design with wide dynamic motion, stationary motors for the X- and Y-axes ensure lower moving masses. In control technology systems, for example, a double motor controller with coupled intermediate circuits exploits braking energy for recovery purposes.

Smooth handling

One million relays a year are produced reliably in different shifts using the Delta robot. Courtesy: FestoThe Tripod robot design “needs less space and design time than a handling gantry and is also faster than a SCARA” (selective compliant articulated robot arm). That is how Gerd Ulmer, general manager of G. Ulmer Automation GmbH, summarized some advantages of the new handling system. He has installed two Tripod handling units on an assembly machine for the automotive components supplier.

On a machine that assembles safety relays for diesel engines, two Delta robots equip the relay bodies with seven to nine contacts, depending on the type of relay required. “The components were previously produced abroad and are now—primarily in the interests of better quality—to be produced on a fully automatic machine which includes automatic test stations,” explains the client, a special machine builder. The machine comprises 24 stations and was ordered from Ulmer by a component supplier to the automotive industry.

Quality awareness

Precise control: The robotic controller CMXR positions tools and grippers in three dimensions and forms the basis for the ready-to-install handling system Tripod. Courtesy: FestoThe machine comprises stations to test individual components and carry out continuity and high-voltage tests, tests of soldering flux dosing, monitoring of the soldering process, and measurement of the contacts fitted to the relay bodies. “A large number of the assembly cells are test stations, with four integrated vision systems,” explains Ulmer.

Thirteen vibration conveyors feed contacts and other assembly components to the machine. It takes only 90 seconds for the contacts and semifinished relay bodies to pass through all 24 assembly stations and emerge as fully assembled and tested relay bodies in a process that includes spraying the bodies in an injection-molding machine and printing them with the date of production.

“To be precise, the machine produces four finished modules every 30 seconds, since that is how quickly the injection-molding machine processes four workpieces,” says Ulmer, describing the performance of his machine.

Flexible, easy teach-in

With the new design “we have been able to produce around one million relays a year in three variants, working in shifts,” reports the system builder. One of the benefits of the handling system is its flexibility, which is easy to program using a configuration tool in combination with a programming language.

“As we received the revised samples of the workpieces for series production very late from our end customer and needed to carry out all programming in-house, we found the uncomplicated and intuitive programming of the robot system very helpful when it came to modifying the functional sequence and component-fitting position at short notice.”

The controller

Thanks to low moving mass and the high rigidity provided by the pyramid-shaped, enclosed design, the robot handling system is highly dynamic but at the same time more accessible than Cartesian handling systems or SCARA robots. The Tripod is actuated by a robotic controller, which can position tools and grippers in three dimensions. The tool tip is guided along the programmed path at all times, even if the orientation of the tool changes. Operation of the system is made easier by the optional handheld terminal, equipped with a touchscreen and keypad. And what’s more, the controller can be used, for example, to link in vision systems such as an intelligent vision system and also handle moving objects.

Equation of success

Customers’ handling tasks determine the form that a solution takes, regardless of the type of drive. Automation experts can help choose among servopneumatic, electric, or pneumatic—on a technology-neutral basis, working on the principle of “Energy efficiency times mechatronics equals success."

Also read: Technologies used in the Ulmer Automation application


- Christopher Haug is with Festo. Edited by Mark T. Hoske, CFE Media, Control Engineering.




The Top Plant program honors outstanding manufacturing facilities in North America. View the 2015 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
Pipe fabrication and IIoT; 2017 Product of the Year finalists
The future of electrical safety; Four keys to RPM success; Picking the right weld fume option
A new approach to the Skills Gap; Community colleges may hold the key for manufacturing; 2017 Engineering Leaders Under 40
Control room technology innovation; Practical approaches to corrosion protection; Pipeline regulator revises quality programs
The cloud, mobility, and remote operations; SCADA and contextual mobility; Custom UPS empowering a secure pipeline
Infrastructure for natural gas expansion; Artificial lift methods; Disruptive technology and fugitive gas emissions
Power system design for high-performance buildings; mitigating arc flash hazards
VFDs improving motion control applications; Powering automation and IIoT wirelessly; Connecting the dots
Natural gas engines; New applications for fuel cells; Large engines become more efficient; Extending boiler life

Annual Salary Survey

Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.

There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.

But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.

Read more: 2015 Salary Survey

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
The maintenance journey has been a long, slow trek for most manufacturers and has gone from preventive maintenance to predictive maintenance.
This digital report explains how plant engineers and subject matter experts (SME) need support for time series data and its many challenges.
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.
Maintenance Manager; California Oils Corp.
Associate, Electrical Engineering; Wood Harbinger
Control Systems Engineer; Robert Bosch Corp.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me