Motion controllers range from single-axis smarts to programmable automation controllers (PACs) that synchronize hundreds of axes and plant IT. These brains of precision motion are at the heart of today’s motion-system innovation. But controls are increasingly advanced in mobile applications as well.
Consider just one example: Trust Automation Inc., known for standard and custom motion and motor controls, is helping design and develop a multi-mission launcher (MML) for a U.S. Army Indirect Fire Protection Capability program. The Development and Engineering Center of the U.S. Army Aviation and Missile Research is leading the project.
The design is a truck-based system that’s fixed or semi-fixed. It holds 15 launch tubes that can fire simultaneously at threats, for 360° protection against unmanned aircraft, cruise missiles, artillery, mortars and rockets. Trust Automation is developing elevation controllers for the MML to give them precise positioning. The controller interfaces with heavy-duty electro-mechanical actuators for motion control to the MML elevation axis. In short, digital signal processing and advanced algorithms enable synchronous control of twin actuators that raise and lower the MML’s pallet.
“These platforms are critically important to national defense,” said Craig Von Ilten, business-development VP for the defense industry at Trust Automation.
Food and beverage example: Controllers make it simple
Consider another example: Opelka’s new continuous pastry fryer is more versatile and easier to clean and service than its predecessor. Called the MagicBaker CleanFlex, it uses B&R automation components for a modular architecture—so end users can use the machine without programming, even after a shutdown to replace parts.
PowerLink allows line or star topology on the equipment, and users can remove networked components without disconnecting the power or worrying about disrupting bus communication. Central data storage speeds up commissioning.
Data coding, motion control, PLC tasks and HMI functions are all on a single CompactFlash card in the controller. When the equipment restarts after maintenance, the controller automatically copies the software (including changes) to related B&R components. More specifically, Opelka leverages integrated PLC/HMI functionality from the B&R Power Panel 500, which has a 10.4-in. touch screen, X20 I/O and ACOPOSmulti drives.
The fryer’s versatility arises from the new control architecture, which allows changes through the HMI panel to accommodate different configurations for different bakers, said Stefan Weng of Opelka. ACOPOSmulti servodrives replaced pneumatic drives on the previous version to eliminate design and operation constraints. Here, a key advantage over pneumatics is that controls can implement new paths during operation at the push of a button without major modifications.
So now, pastries go through the machine more gently and with greater precision. That in turn means that users can customize the machine for different pastry types … simply by picking recipes on the HMI. So the machine can now float or tip pastries into the oil bath.
The new machine’s drives are synchronized electrically, which means the oil bath can extend as needed without making the engineers modify the power-transmission system. There’s also a Power Panel 500 in a control cabinet within the machine body. The drives for other machine modules (including one for loading separate raw-dough forms into rows and another at the end of the line that injects jelly into the pastries) are in distributed control cabinets.
“Space is limited in the distributed cabinets, so the compactness of the ACOPOSmulti and X20 modules was key,” said Weng. A two-axis variant of the ACOPOSmulti was the biggest space saver of all. Opelka saved even more cabinet space by replacing dedicated power supplies with 24-V modules from the X20 system. The X20 system also provided digital and analog I/O slices, as well as PT100 input terminals for PID temperature control.
The X20 modules also control stepper motors that move pushers and other small machine axes. “The X20’s three-part construction has a terminal block, electronics module and bus module. This simplifies installation and allows electronic-module replacements without the hassle of rewiring,” said Weng.
X20 modules and drives communicate with each other and the central controller through PowerLink.
Another improvement is that the user can configure components without needing to connect each to a PC first. To prepare the components for bus communication, the engineer just sets their node numbers with DIP switches before install.
During operation, PowerLink and the electronic drives also make decoupling machine modules easier. The user simply disconnects the power and PowerLink cables, both of which handle repeated plugging and unplugging much better than compressed air hoses. Then machine modules can go to a washdown room for cleaning.
PLCs control San Fran hangar doors
Door motors, controls and gear drives of the Superbay Maintenance Hangar at the San Francisco International Airport needed a retrofit. Previous controls were built in 1969 with relays, contactors, timers, antiquated power tracks and miles of wiring requiring continuous maintenance. The massive hangar has two 130-x-90-ft doors, weighing 74,000 lb, on either side. Each door consists of an inner and outer panel for a total of eight independently functioning doors. The door sections mounted on rails offset so that adjacent doors can open and close without interfering with neighboring ones.
MicroSmart Pentra PLCs from IDEC now control and monitor the doors, letting airplanes as large as a 747-400s in and out of the hangar. Engineers from San Francisco International Airport’s Design and Construction Dept. used IDEC PLC programming and PLCs for their simplicity and expandability. Twin drives power the doors’ halves. A VFD drives each motor door, in turn capable of moving the entire door (though airport engineers made each drive redundant).
An IDEC MicroSmart Pentra PLC connects to each doors’ two VFDs through Modbus, and communicates in ASCII through an RS485 connection. The PLC also has inputs for switches and sensors for preventing operation when people or objects are in the way. From the IDEC HG4G’s HMI, operators open and close the doors.
The eight centralized PLCs controlling the eight doors simplify operation; soon a master PLC could control all the doors and command the PLCs as slaves. Wireless connection will soon provide fire control. In the current design, anytime a door stops, its PLC analyzes the problem and displays a troubleshooting protocol on the HMI.
The IDEC MicroSmart Pentra PLC has floating-point math functions, supports 32-bit processing, Modbus master and slave capabilities, up to 512 digital I/O and 56 analog I/O. The PLC also connects to the Internet (to allow for mobile access). IDEC Automation Organizer software comes in WindLDR for programming in ladder logic and function blocks (and online editing and simulation) or WindO/I-NV2 for programming HMIs. WindO/I-NV2 has tools for programming HMIs with a 5,000-symbol library (to save design time).
The hangar engineers used Automation Organizer to program touch-screen controls, status and troubleshooting displays, alarms, feedback processing and drive operating hours for maintenance purposes.
Simulation with the IDEC system let the engineers start and fine-tune the first door’s operation in less than a day (with the others in operation within a few hours). It also let the engineers add interlocking man doors to the giant hangar doors—standard doors are embedded in the hangar doors for aircraft mechanics to enter and leave the hangar. Then the engineers programmed the PLC and HMI to interlock these man-doors with the larger hangar doors. If any man-doors are open, the HMI indicates that and prevents operation.
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