New tools that enable servomotors on machines to be tuned quickly and more accurately can give a competitive edge to machine builders trying to be first to market with new designs for their customers.
The new Mitsubishi Electric AC servo system, MR-J5, includes built-in tuning functions in the servo amplifier. It automatically performs easy-to-use quick-tuning capabilities that control vibration and overshoot simply by turning on the servo-on command.
The servo amplifier automatically sets control gain and machine resonance suppression filters and inputs torque values to the servomotor. No tuning experience is required since gain values are automatically generated. This allows the servo amplifier to start operation normally, reducing machine setup time and effort. The entire operation takes just 0.3.
“It’s what we call tuning for the real world, because it enables an OEM to input motor values based on the load that will be on the machine when it’s in actual operation,” explains senior product marketing engineer Elaine Wang.
“Historically, suppliers have based tuning advice on theoretical values. That often required OEM electrical and mechanical engineers to spend days making repeated fine adjustments and doing manual calculations to arrive at the proper operational set-up,” she says.
By basing its automatic tuning function on typical future loads, the new tuning software shortens the engineering work needed to get the equipment operational and gets the set-up process within close range of the machine’s ultimate requirements. Mitsubishi’s software manages the calculations, which are based on general values that are correct for most applications.
In addition to the quick-tuning function, which enables a stable positioning operation, there’s a one-touch tuning option to enable very responsive positioning. There’s also a manual tuning function for machines that require very precise tuning, such as printing equipment.
Quick tuning also minimizes incorrect torque values, which can cause machines to generate a high-pitched noise. This would be particularly undesirable in a medical setting.
“Good tuning values enable machines to make products faster,” explains Wang. “When making and filling a pouch, for example, you can achieve faster cuts and more accurate positioning, which allows you to better control mechanical components. Better tuning values ultimately result in increased output.”
Applications that require great precision, high volumes or high speeds, such as printing, packaging, automotive, semiconductor manufacturing and machine tooling, would significantly benefit from the quick-tuning capability of this new servo system, enabling machine builders to get their new designs to market faster.
The system also incorporates a patented vibration function on both the load and the machine base at frequencies as low as 100 Hz. This enhances high-response motion and improves productivity in a multi-inertia mechanism.
The new servos, which can control motors up to 10 HP, and up to 30 HP by 2021, have a compact design allowing multiple controllers to be mounted side by side to minimize enclosure size. They can accommodate a wide range of axis requirements, from a single axis to a 258 multi-axis system, with up to three axes in one servo unit. This helps reduce energy consumption and maximizes cabinet space with less wiring.
To increase the flexibility of system configuration, the MR-J5 servo series accommodates both CC-Link IE TSN, a 1 Gbps network that enables time synchronization across all connected devices, including servo amplifiers, motion modules, I/Os and PLCs, and EtherCAT, allowing for a communication cycle of 125μs and pulse train connection at a pulse frequency of 4 million pulses/s.
The servo amplifiers provide predictive maintenance services powered by AI technology, improving machine uptime by detecting mechanical component deterioration through friction and changes in vibration values, and will generate a warning in advance of failures.
“This is a complete servo system with quick-tuning and other advanced features that deliver high-speed, high-precision control to maximize machine performance, providing increased reliability, versatility, flexibility and efficiency,” adds Wang.