AEMK Systems, based in Waterloo, Ontario, Canada is an innovative provider of high-speed, vision-based robotics systems for applications in the food industry, packaging and automated warehousing. AEMK was established to commercialize the results of research at the University of Waterloo involving high-speed robots. The AEMK robots use cables instead of rigid arms to reduce moving inertia and mechanical equipment cost. Due to their simple design, AEMK robots can be installed in many labor-intensive applications with high capital cost barriers to incorporating automation equipment. "AEMK strives to provide customers with the most cost-effective robots possible with simple integration, low maintenance cost and outstanding customer service," says Amir Khajepour, AEMK president and University of Waterloo professor.
The culmination of these technological advances is a revolutionary, high-speed robot capable of more than 120 pick-and-place cycles per minute. The three- and four-axis models of these robots are dubbed DeltaBot, and use passive cables to control the movement of end effectors. This design permits the robot's workspace to be easily scaled to any application.
To boost control performance while reducing cost, AEMK's DeltaBot line was recently upgraded with Beckhoff CX1010 Embedded PCs running TwinCAT PLC software. "We wanted the smallest possible footprint for the controller that would also give us the most programming flexibility. We decided that the CX Family of Embedded PCs was the best suited solution," Khajepour says. The DeltaBot is also now equipped with EtherCAT I/O terminals, as well as the EtherCAT-enabled AX5000 Servo Drives installed above the pick-and-place unit.
"Considering the DeltaBot's previous PC-based controllers, the upgrade to an improved PC-based platform was the natural progression. Our previous experience indicated PLC-based platforms are highly deterministic in nature and precise, but are lacking in flexibility and ease of programming," Khajepour says. "The TwinCAT PLC software platform from Beckhoff brings all the best PLC features into a flexible PC-based package."
The DeltaBot moves extremely fast; most paths must be completed in less than 500 milliseconds. "This permits little time for communication jitter, even in the range of milliseconds," Khajepour says. "Fast access to the I/O and ease of integrating remote I/O are areas where EtherCAT has been exceptionally useful for AEMK. Also, the AX5000 drives were instrumental to accommodate a wide range of power requirements, drive communication at 'EtherCAT speed' and low cycle times. We eliminated the jitter introduced by the communication with external DLL libraries and went to a full implementation of our path generator, libraries and a feed forward PID control loop directly in TwinCAT."
Multi-channel EtherCAT communication, low cycle times and flexible architectures allow AEMK to run the AX5000 in position configuration, which in combination with NC functionalities employs a very effective PTP positioning system. "The DeltaBot can run in velocity mode without adding a burden to our control system communication when equipped with the AX5000," Khajepour says. "Also, numerous Beckhoff servo motors are available with a wide range of voltages."
AEMK Systems successfully implemented DeltaBots in several projects and introduced the robots as stand-alone products to the market. "Because of its reliable nature, the new DeltaBot has greatly reduced testing and integration time. Considering TwinCAT's ease of programming, DeltaBot development time decreased by almost 50 percent," Khajepour says.
AEMK now uses TwinCAT PLC and Beckhoff Embedded PCs as the standard control platform for all projects. "Our goal at AEMK Systems is to offer flexible automation and Beckhoff offers the ideal solution to run, communicate and interface with nearly any industrial device that we could utilize. The Beckhoff architecture will help make it the preferred robot solution for many cost-sensitive applications," Khajepour says.