It's no secret that one of the major trends in automation and controls has been the increasing availability of robots for price-sensitive applications. Arguably, the next logical step is to bundle these less-expensive robot technologies with industry-specific solutions that continue the promise of affordable performance.
Empowered by high-performance and open PC-based control technologies, Houston-based ARC Specialties aims to deliver more affordable custom robot solutions to automated applications.
Although the company serves a diverse range of industries, some 90% of ARC Specialties' systems are deployed in the oil and gas industry. We count several globally active oil and gas OEMs headquartered in the Houston area as significant customers.
To create the most advanced solutions possible, we have a full-featured lab to test and demonstrate new ideas, and a skilled team of craftsmen to fabricate, machine and assemble the equipment. "The ARC Specialties team strives to manufacture best-in-class custom automation equipment with standard, off-the-shelf technologies that ensure long-term availability," says John Martin, senior project manager, ARC Specialties.
For 29 years, ARC Specialties has designed, developed and commissioned automated systems to increase manufacturing efficiency and improve product quality. Because of this history, the company was commissioned to create a fully automated robotic welding system for assembly of fluid-purification products.
The project challenges were unprecedented: one machine that would include large-product manipulation, robotic assembly, robotic welding, fixturing, servo motion control, and simplistic operation. Along with the technical challenges, there were manufacturing requirements that included reducing cycle time, improving product quality, and lowering unit cost. The system also needed to handle a wide range of other highly automated tasks throughout the manufacturing process.
ARC Specialties responded to the challenge by creating a customized, automated robotic system called the ARC-11RB (Figure 1). The system's various automated processes included an accumulation and indexing system for raw and completed materials. A large inverted pick-and-place gantry with three axes of motion that could rotate 180° manipulated the product in and out of the automated fixturing. Custom, servo-controlled, three-jaw chucks accurately fixtured and positioned the product during assembly. Smaller end rings were assembled using a robot equipped with pneumatic end-of-arm gripping devices. Automated, quick-change tooling allowed for robot end-of-arm tooling selection between multiple gripper sizes and welding torch. Robotic welding with real-time procedural override finished off the automated fabrication process.
All of this was integrated into one embedded PC-based control platform that allowed for single-point control. "The ARC-11RB automated system incorporates many of the same components we use on our standard products," Martin explains. "Using our past experiences, we were able to provide a solution to a very complicated task that is simple to use."
The project advanced through ARC's preferred path, starting with a proof of concept and weld procedure development on a robot inside ARC Specialties' R&D laboratory using the customer's actual product. Once we proved the concept, we went to work bringing the system to life using complete in-house design and manufacturing capabilities. ARC mechanical engineers designed the various material loading and gantry structures while programmers created procedures for the robotic arm. Simultaneously, ARC's adjacent manufacturing facility fabricated the system, machined customized tooling required for precise fit-up, and wired electrical panels. After completion, we invited the end user to our shop for demonstration of the system before shipment. What they witnessed was a system that exceeded their expectations.
PC Provides an Edge
Our company's control philosophy is centered — by design — on open systems. "Many of our competitors manufacture their own proprietary controls," says Gary Ewin, ARC Specialties' chief electrical designer. "That can be a fine solution for a few years, but some years later this can be a major problem, considering support and repairs needed to maintain the control system."
We're a builder that incorporates PLC, CNC, PC and robotics into our turnkey automation systems, ranging from process controls to multi-axis coordinated motion applications. "We have systems operating all around the world and have been providing automation solutions for more than 28 years," Martin says. "In the past, we would have used PCs to run the user-interface applications, while a PLC or CNC ran the machine control. Now, with a multicore PC, we run all of these applications on one piece of hardware that sits inside an environmentally controlled enclosure, and have an inexpensive monitor exposed to shop floor conditions."