Upfront design saves designers time and effort, and reduces many problems that arise later in a machine's lifecycle. This article introduces 10 very useful techniques in machine control design. Have you ever had the experience of complaining that engineers didn't fully consider the user experience when designing a machine? To help engineers design easy-to-use machines, this article introduces 10 design techniques covering automation, control, instrumentation, sensors, logic devices, and communication technologies. Once you master these 10 techniques, engineers can save significant time and effort in the design process and avoid many potential future problems. 1. Investigation, Research, and Quantification Gathering information, making plans, and then meticulously moving towards the established goals. This is a typical machine design process. In pursuit of high product flexibility and adaptability, engineers often spend a lot of time and effort adding new features, ultimately leading to overcomplication. Michael Gurney and Ed Diehl, founders of industrial systems integrator Concept Systems, explain, “In product design, once priorities are established, you should immediately start with what’s most cost-effective. Statistical analysis of process and quality control is extremely useful information.” “Modular machine design and manufacturing methods can meet the growing demand for customized designs while shortening machine development time and reducing manufacturing costs for OEMs,” says Larry Komarek, Automation Product Manager at Phoenix Contact. Komarek further suggests, “Break down a machine or series of machines into different functional components, each with corresponding mechanical, automated, and software programs. Combining these functional components allows you to create customized configurations or ‘small/medium/large’ product series. Pre-designed, pre-documented, and pre-tested functional components can be produced quickly, reducing production costs.” 2. Standards and Safety Gurney and Diehl point out that with standard, universal interfaces, products can integrate optimal system components while reducing the obsolescence and obsolescence of dedicated control systems. Knowledge accumulated in design software can be translated into machine code, thus avoiding modifications to design parameters. Some design software provides data converters for STEP and IGES file formats. STEP, or Product Model Data Exchange Standard (ISO 10303), defines how to describe and exchange digitized product information. "When designing distributed control systems, make full use of Clause 430.53(c) of the NEC code's group motor installation provisions. This reduces the number of branch circuits, lowers costs, eliminates EMC noise, allows for the replacement of functional modules without rewiring and debugging, and enhances product flexibility," explains Rich Mintz, Electronics Product Manager at SEW-Eurodrive. Larry Sunday, Machine Safety Product Manager at Schneider Electric, said, “In terms of safety, since the 2002 revision of NFPA-79, all general-purpose machine designs should comply with IEC 60204-1 Category 4. It is the highest standard of safety specification, requiring all machine designs to consider safety relays and safety interlocks.” He added, “The 2002 revision unified the NFPA-79 and IEC 60204-1 international standards. The common practice in the US is to use standard relays in basic control circuits to ensure so-called ‘control reliability.’ But this is far from sufficient for the IEC 60204-1 Category 4 standard.” 3. Sensors and Machine Vision “Don’t wait until the late design stage to consider sensors. Small, intelligent sensors often bring unexpected benefits. With component baseboard space already determined, a cost-effective sensor can sometimes solve big problems,” said Joseph Dolinsky, Technical Marketing Manager at Banner Engineering. Mark Sippel, In-Sight Vision Sensor Product Marketing Manager at Cognex, points out that the approach to handling detection and process feedback depends on many factors. These factors include: Does feedback information need to be shared across multiple discrete detection, suppression, or other systems? Is a controller needed to coordinate detection results with auxiliary tasks? How are detection results communicated and used? If I/O devices are used for communication, what types of other control ports are available, and where are they located? Factors such as lighting, power, and data transmission also need to be considered. [ALIGN=CENTER] Figure 1: SpanTech (a transmission equipment OEM) demonstrates speed and flexibility when reconfiguring its production line using SEW Eurodrive's modular distributed control technology. 4. Logic Platforms for Hardware and Software Rahul Kulkarni, Product Manager for Industrial Data Acquisition and Control at National Instruments, says, “The first step in the long journey of machine design is choosing the right logic platform. Commonly used controllers include PLCs, PC-104s, PCIs, PXIs, or conventional circuit boards. Before deciding on a controller platform, it is essential to fully consider all the functions the controller will perform (e.g., logic control, process control, motion control, automatic detection, and machine status monitoring). Programming tools should be easy to learn, and the generated code should be modular, easily upgradeable, and reusable.” Dan Seger, Global OEM Technical Consultant at Rockwell Automation, explains, “Choosing a control architecture solution simplifies the design process. From controllers and networking technologies to peripherals and operator interfaces, choosing components solely based on minimizing procurement costs will create problems later in the development process. Similarly, good connectivity (e.g., tightly packed, interconnected components) can improve efficiency and reduce costs. Conversely, using inexpensive device communication solutions in the design will not only be difficult to use but will also consume significant time during the initial and maintenance phases of engineering.” "To achieve the best results, he recommends separating the programming work for control and information sharing. Other valuable practices include structured data formats, drop-down menus, and code-based object libraries categorized by function. 5. Actuators Select appropriate pneumatic, hydraulic, or electric actuators based on application requirements. Similarly, the motion controller also needs careful selection. So, can a motor control unit (MCU) or a digital signal processor (DSP) be used for motor control? Kedar Godbole, a motor control strategy expert at Texas Instruments, suggests seeking performance innovation and reducing system costs, striking a balance between performance and price (achieving optimal cost-effectiveness), using an efficient C/C++ kernel in rapid software development, using flexible and easy-to-use tools, and achieving a high level of analog integration. Jan Lindholm of SEW-Eurodrive says, 'Control mechanisms are often more suitable and efficient than mechanical friction mechanisms. Compared to similar solutions such as clutches and brakes, frequency converters (especially closed-loop ones) can extend cycle times by 2 to 3 times while reducing equipment wear and maintenance costs.'" Lindholm further explained, "Combining variable frequency drive technology with sensorless vector control, flux vector control, and AC brushless servo systems can solve many motor drive problems." 6. Display Screen vs. Buttons: Which is Better? Which is better, a display-based Human-Machine Interface (HMI) or buttons? The answer is: using a touchscreen instead of buttons is beneficial. HMI toolkits come with highly adaptable and reusable templates. Joe Rubino, Software Product Marketing Manager at Omron Electronics, explained, "HMIs also have other advantages, such as data interconnectivity and diagnostic capabilities. Diagnostic capabilities can bring advantages in machine hardware and software uptime, ease of connectivity, and reduced programming workload, making them truly worthwhile." 7. Networking and Communication Using network technology can reduce the workload of internal and external wiring and communication decoding. David Crump, a marketing expert at Opto 22, explained, "Machine-to-machine (M2M) communication technology enhances machine connectivity." Wireless technology enables the connection of machines to enterprise information systems, allowing for remote equipment monitoring and startup, real-time production status reporting, and other operations. M2M also helps machine designers track machine lifecycles, identify fault points, and improve future designs. Simultaneously, M2M can create more revenue opportunities for enterprises, such as providing value-added services like proactive equipment maintenance and repair. “There are many types of wireless technologies,” said Kulkarni of NI. “For M2M communication between remote computers and factory HMI/SCADA systems, satellite or cellular communication should be used due to transmission distances of hundreds of miles. For communication between controllers/PLCs and HMI/SCADA systems, IEEE 802.11 wireless communication technology is most suitable. However, for communication between controllers and sensors, Bluetooth or Zigbee technologies are more effective due to transmission distances of only 10–100 meters.” Seger of Rockwell Automation pointed out, “(When designing communication between different devices) avoid using RS-232 and standard Ethernet technologies, otherwise a lot of time will be spent writing dedicated communication drivers to support data transmission.” This is a time-consuming and labor-intensive task that doesn't add value. However, for the internal machine components, using a secure terminal technology at the I/O level can save assembly and maintenance time. "Wago's screwless cage-clamp terminals offer greater flexibility, reducing wiring time by 60% and eliminating the need for machine hardening every 6 to 8 months in some applications," said Dean Norton, Marketing Manager at Wago. "This wiring technology allows for pre-wiring to meet all machine I/O requirements and facilitates controller communication using appropriate bus protocols later in the design process." "[ALIGN=CENTER] Figure 2: Wago, a company that provides cage spring clamp terminals/wireless terminals, says that using screwless terminals can save 60% of wiring time.[/ALIGN] 8. Power Supply Purchase power systems directly instead of trying to design them yourself to save significant time and effort. Power supplies, buses, management systems, and intelligent components can all report to the HMI, resulting in greater system integration and efficiency. Isolation, monitoring, and shielding measures ensure minimal transmission lines and EMF interference. 9. Integration Considering machine design from the perspective of the entire production process can greatly improve efficiency. Fredrik J. Smithson, CEO of FlexLink Systems AB, says, "Typically, a machine production line only utilizes 30% of its capacity. If the machine design is considered from the perspective of the entire production process, then the utilization rate of the production line will be greatly increased." "Combining information from machine tools can generate more benefits than the machines themselves. Some major engineering and manufacturing organizations have indicated that STEP databases can reduce production planning and manufacturing control costs by up to 35% and 75%, respectively (Source: Step Tools Inc.). 10. Timely Project Summary As a project nears completion, it's advisable to take some time to evaluate and summarize it to facilitate the next round of design."