Today, an increasing number of automatic adhesive applicators are used to apply glue and sealants in automated production lines worldwide. F Corp., a manufacturer and seller of these applicators, was developing a new model that supports EtherCAT. Mr. H of F Corp's system development department said:
"After major manufacturers started using EtherCAT, more and more EtherCAT-based equipment has been used in industrial production lines. So, we decided to develop an EtherCAT-based model for wider compatibility with other equipment, and it required an EtherCAT-based motion controller."
Another challenge of the new model development was machine downsizing.
"With our previous system with a PLC, it was necessary to add a pulse train unit and a driver for each additional motor axis," explained Mr. H. "With this expansion, the amount of wiring would increase, as would the size of the power distribution board space for housing it. This system configuration was a bottleneck for system downsizing."
It also needed to improve the machine cycle time, requiring faster motion than the previous model. The function of automatic adhesive applicators is to efficiently apply a specified amount of adhesive to a specified position. The target for application is not limited to straight lines, but also includes a variety of curves. So, adhesive applicators were required to draw trajectories with precision while adjusting the position and speed of multiple motors.
Convinced that an EtherCAT-based motion controller would be needed to achieve this trajectory control, Mr. H started looking for one. But it was not easy to find one that met his requirements, and he became stuck.
Seeking a solution, Mr. H consulted a SANYO DENKI sales representative who visited F Corp. for a regular meeting on a separate matter. They discussed F Corp.'s current problems and system requirements in detail. At a later date, the sales representative proposed their SANMOTION C S100 motion controller.
"The SANMOTION C S100 motion controller supported an EtherCAT-defined Cyclic Synchronous Position control mode," explained Mr. H. "With this function, commands can be sent to each axis in a 2 ms cycle time. EtherCAT controllers from other companies only provided a profile position control mode. These were able to specify the coordinate and speed of target positions, but unable to control the trajectory during positioning. We expected that the SANMOTION C S100 motion controller could improve our adhesive applicator's cycle time without sacrificing precision. In addition, we also expected it to help us build an IoT(2)-ready system with the web server function that enables operational status monitoring and program variable read and write via a standard PC web browser."
The sales representative also proposed a space-saving combination of the SANMOTION C S100 motion controller and a multi-axis system.
"He showed me an example where they minimized the controller space by combining the SANMOTION C S100, the industry's smallest motion controller, and the SANMOTION Model No.PB multi-axis closed-loop stepping system," continued Mr. H. "Our previous adhesive applicator used three drivers to control three motor axes. The proposed combination with SANYO DENKI's SANMOTION Model No.PB multi-axis closed-loop stepping system, however, enabled us to control three motor axes with just a single driver. The EtherCAT communication took only one cable, requiring much less space for wiring. As a result, we estimated that the space for the controller could be reduced to 1/3 that of the previous system."
Soon after the proposal, with the support of SANYO DENKI, Mr. H conducted an evaluation of their prototype in combination with the SANMOTION C S100 motion controller.
"The result was really stunning," recalled Mr. H, with excitement. "We realized a great space saving with EtherCAT capabilities. Furthermore, it shortened the machine cycle time while maintaining the adhesive application precision. In addition, maintenance man-hours were greatly reduced thanks to the reduced wiring. Our product has received high ratings from our customers. The credit goes to SANYO DENKI. Really."
(1) Compared with digital I/O motion controllers on the market capable of sequence, motion, and robot control in one unit. Based on our own research as of October 10, 2018.
(2) Internet of things: A system that connects electronic devices to a network so that they can communicate, interact, and be mutually controlled.