Introduction The decade of the 1990s is considered an era of rapid development in PC-based technology. This rapid growth in PC-based hardware and software has been of great significance to manufacturing, from order entry and system analysis to production line process control. With the advent of the Intel Pentium processor and Microsoft Windows NT, manufacturers now have a truly open architecture, a non-proprietary control environment to utilize. This environment supports (in fact, facilitates) extensive system integration across different manufacturing equipment. It also allows manufacturers to easily develop user applications to support their processes and gain experience from third parties in off-the-shelf software packages. More importantly, PC hardware and software platforms are built on industry-acceptable standards for hardware components and software. The benefits of adopting standards have been proven in the computing industry. These benefits can be easily transferred to the factory floor and control industries. This open architecture environment provides a range of manufacturing-specific functions for system control, process monitoring and data acquisition, quality management, and communication with other systems—previously impossible—typically closed-loop structures, specialization, and computing platforms for manufacturing. The main benefits of PC-based manufacturing based on an open architecture are: * Communication * Connectivity * Component standardization and availability * Cost savings. Open PC control is creating new opportunities for “plug-and-play” adaptation of existing mechanical systems such as robots, machine tools and automation systems, and providing a large market for the modification and upgrading of capital equipment. One of the earliest examples of truly open components and communication protocols appeared in the field of robotics. Some of the Fortune 500 companies that are now using PC control in production have taken a proactive approach to PC-based manufacturing to realize the various advantages of PC technology in the production field. Saturn is now among the leaders in applying PC technology to manufacturing [1]. At Saturn, a one-minute production stoppage costs $4,400. Saturn determined that it needed access to the most recent 100,000 different types of manufacturing information to develop better production processes so that its manufacturing systems could run without interruption. By simply using industry-standard hardware and software, Saturn has implemented a PC-based strategy and a production system that is truly integrated with finance and administration in vehicle systems, body systems and powertrains. The company chose Microsoft Windows NT for its security measures, graphical user interface and open architecture. At Saturn, the PC-based open architecture and Microsoft Windows manufacturing environment have proven their capability in handling critical tasks such as dynamic paint job scheduling, production tracking, and quality monitoring. The system also automatically collects 90% of the necessary manufacturing data to evaluate various production processes and make continuous improvements. User applications have been developed using Microsoft Visual Image Basic or Visual C++ to capture production and downtime data for maintenance reporting, overhaul, and testing systems. The company has even developed various in-machine tools for remote performance monitoring. The "automation silos" that have plagued the workshop for the past 20 years due to the implementation of proprietary computer-based technologies are disappearing as original equipment manufacturers (OEMs) agree to industry-standard protocols for hardware, software, control, communication, and operation. The exception is robotic automation. Proprietary control architectures limit robot application development to simple, stand-alone tasks. It has been shown that dirty, dark, and dangerous tasks from which flexible automated robotics can yield significant benefits are simply impossible to develop and integrate cost-effectively. Complex applications such as adaptive multiple welding using arc-penetrating and vision sensors, or the application of adhesives to bonding materials, are being developed within Fortune 500 companies. These large companies can afford the research and development budgets, staff experience, and extended R&D time required for dedicated robot controllers. However, such “advanced” systems are not intended for production. The cost of integrating, installing, and maintaining such experimental robot work cells is prohibitive for factories. Even in simple, well-defined task scenarios, dedicated robot control architectures alone increase system implementation costs. In most cases, this hinders the realization of the benefits of the latest developments. This is simply unacceptable given the 115,000 robots already in our North American market and the more than 15,000 new robots installed annually. According to Fortune 500 manufacturers with 50 (or more) robots on their production lines, the average final implementation cost of a single robot work cell is 3 to 5 times the quote for a standalone robot and controller. The additional costs come not only from the purchase of peripherals and tools but also from the integration of installation and hardwiring. This means that a $50,000 robot and its control system are expected to incur an additional $150,000 to $250,000 (or more) in costs during the setup and operation of a work cell. These costs are only listed as a detailed item under the "Capital Grant" program. There are other unavoidable expenses. These expenses are hidden within (or sometimes not included at all) other budgets such as engineering, maintenance, spare parts, and training. For example, programming (or reprogramming) a work cell can take weeks to months. Operator training may take up to eight months. Spare parts inventory can account for 20% of the work cell cost, thus impacting production downtime. The actual price invoices can be staggering, and replacing an existing robotic arm in production with a new unit can cost even more. Basic robot trajectories, tool racks, I/O, and mechanical interfaces are generally different, requiring new research and engineering. Extending the lifespan of robotic equipment with PC-based control . Since the advent of robotics, more than 115,000 robots have been installed in manufacturing facilities in North America alone. Most of the initially installed robots are still in operation. Similar to machine tools (which can have lifespans of decades), robots are increasingly proving their mechanical reliability, usability, and rationality based on their long lifespan. Some reports indicate robots have used 50,000 hours before major overhauls; however, on average, robot controllers become obsolete every seven years, requiring original equipment manufacturers (OEMs) to introduce a new type of controller. It's not uncommon for a robot manufacturer to introduce a "next-generation" robot with a new controller using a new programming language. This new controller is not backward compatible with previous control systems. This means existing robot programs cannot be used on the new system and must be reprogrammed for the tasks at hand to run on the new system. End users can only avoid reprogramming costs by applying the new system to new workstations and production lines. This strategy is only viable in cases of equipment expansion and new installations. However, until now, there has been no good strategy for upgrading existing robots with new controllers. The obsolescence of the robot/controller group is creating a significant financial and productivity barrier for manufacturers trying to continuously improve their competitiveness, but they are limited to using computing and control technologies from the 1970s and 80s. The ultimate choice made by robot OEMs is to no longer support older controller models once a new generation of controllers is released. As a result, users of earlier robots now find it difficult to find spare parts for their robot controllers. Some older robot controllers used as many as 50 dedicated printed circuit boards. Because the controllers are no longer supported, replacement circuit boards are no longer available from OEMs. Spare parts must be obtained from reseller inventory. Replacement parts for some models (such as those used in the Cincinnati Miraclone robot series) are extremely scarce. In fact, this is because OEMs are no longer involved in the robotics business. If a replacement part is available, it is very expensive. This problem of obtaining spare parts is so prevalent in the robotics industry that the price of an old “orphan” controller, based on the possibility of utilizing discarded parts, now approaches $20,000. Changing Targets Unlike other sectors of the machine tool and automation equipment industry, the robotics industry has not yet adopted any computing, control, or language standards. Each robot manufacturer provides its own proprietary technology, and due to the constant changes in robot manufacturing and imitation, the implementation of proprietary technology still lacks a generally minimum licensured PC industry standard. As a result, the robotics industry can readily utilize PC technology. The Dilemma of Capital Investment Manufacturers who have been using robots for 10, 15, or 20 years now face a significant dilemma. They have invested heavily in robots whose mechanical parts are still in good working order during production. Investments in robot hardware, installation, peripherals, other tools and equipment, and training have little hope of meeting the manufacturing demands of 2000. Controllers cannot communicate with other equipment on the shop floor or throughout the enterprise. Controllers also cannot connect to new robots of the same brand. Original equipment manufacturers no longer require support for these controllers, making it difficult to find spare parts to make them work. PC Control Strategy Retrofit outdated robot controllers with a PC-based, open architecture, plug-and-play solution. This includes price/performance breakthroughs on the PC platform. Utilizing the processing power of Microsoft Windows NT. Employing an open system architecture. Supporting various communications. Simplifying operation, training, and maintenance. Automating data acquisition and distribution. Specifying and enforcing various standards. Rearranging production line robots with minimal production downtime. Retaining existing, proven work cells, fixtures, and tools. Relocate existing robots to new work units and production lines to maximize previous investment returns and minimize future capital equipment expenditures. Expand your capital investment. A PC-based Open Architecture Controller The world's first truly open architecture robot controller, running on Windows NT and based on an Intel Pentium processor, was introduced in July 1997 by Robot Workspace Technologies (RWT). In December 1998, RWT launched the second-generation URC controller. The Universal Robot Controller (URC) represents a significant technological breakthrough in factory automation and machine motion control. It is specifically designed for plug-and-play overhauling of existing robots to facilitate simple and cost-effective modernization of motion control technology. Due to limitations such as dedicated hardware, limited options, and single resource suppliers, the performance of the URC far exceeds the performance levels of controllers offered by new original equipment suppliers today. The main benefits of this PC-based open architecture control are: * Communication * Connectivity * Components * Cost. Overview of the Second-Generation URC All hardware and software used in the URC system are standard off-the-shelf components available on the market. Fully integrated into a truly open architecture platform, the URC features an Intel Pentium processor, a touchscreen user interface, and a simplified operator teach pendant. The latter maximizes the use of Microsoft Windows software. Compared to traditional robot controllers, the power module containing all the robot's electromechanical interface systems is a very small box. It can be placed near the robot within the work cell. The URC, equipped with a PC, robot logic circuitry, touchscreen, and keyboard, serves as the operator interface and can be installed anywhere accessible, inside or outside the work cell. The new architecture provides distributed control and even the functionality of PLC logic. The URC's state-of-the-art features include internal networking, connectivity with existing automation systems, and remote connectivity for monitoring and reporting. Microsoft Windows NT allows users to customize the user interface. User applications can be easily developed using languages ​​such as Microsoft Visual Image Basic or C++ to automate data acquisition and run distributed routines. The URC will also run any third-party PC-based software to support, for example, ISO 9000 and other manufacturing initiatives. Several advantages of the URC configuration include: URCs can be easily integrated with multi-power modules and other control systems to support a distributed control architecture. In fact, URCs can be installed before deploying work cells for easy enterprise-wide system integration. URCs can also be used as a training console, a configuration that translates into significant cost savings for end users. This is because it reduces the number of trajectory power blocks, minimizing land use on the production floor. URCs also save on system integration, training, and spare parts inventory costs. The standard programming language Robot Script™ is used for programming any robot employing a URC. It is based on the industry-standard Microsoft Visual Image Basic language but with extensions for robot control. Robot Script supports all control structures and variable types, enabling the creation of complex applications for data processing, I/O operations, and robot control. Motion planning, data processing, and servo control are all embedded within simple, intuitive English commands. The motion control system supports a wide range of manipulator configurations, including joint, linear, tool, and circular motion modes, coordinate systems, absolute and relative positions, tooling, and continuous and point-to-point motion. The flexibility of the robot system stems from its programming capabilities. In reality, all robots are programmed using some type of robot programming language. These languages ​​are used to command robots to move to specified positions, output signals, and read input. Currently, there is no standard robot language, so each robot manufacturer develops its own, each with its own syntax and data structure. This trend is destined to continue. Robot Programming Language Barriers Many factors lead users to purchase robots from multiple manufacturers. As a result, multiple languages ​​run within the control system. This requires robot programmers to be proficient in multiple programming languages, or at least proficient in certain languages. This diversity necessitates a common language that can be used for any type of robot. Using Microsoft Windows NT offers great flexibility in software design, and more importantly, it allows access to thousands of existing software programs. It is also an operating system familiar to many, thus requiring less learning time. Microsoft's Visual Image Basic language family includes Visual Image Basic Description Version (VBScript). It was originally developed for use on the Internet as a way to attach dynamic content to web pages. Currently, VB Script is included in Microsoft Windows 98 as a batch file language and will also be part of the next version, Microsoft Windows NT. All the syntax based on the graphical representation of the Basic language is very easy to learn. The commands used are similar to English, making the entire program easy to trace and debug. Robot Script is a VB Script with an additional command library specifically for robots. The semantics of these commands are written in a syntax that matches the native VB Script commands. This is also designed so that even users less familiar with robot programming can learn the language relatively easily. By establishing a language driver for Microsoft ActiveX controls, Robot Script can also leverage the open architecture of Microsoft Windows. Microsoft ActiveX controls allow software developers to embed existing technologies into their products. This allows users to develop a standard user interface that, in addition to any other features added by the developer, can run, stop, and pause the execution of the robot program. In this way, Robot Script programs can practically communicate with any other software (if someone writes a program to establish communication between Robot Script and that software). Robot Script is a general-purpose robot programming language. Once a robot programmer learns RobotScript, he or she can write programs for any robot that connects to a universal robot controller. A program generated for one robot can be used for different robots (assuming all teach points are within the effective working range of both robots). A recent real-world example of PC-based robot control is Robotic Workspace Technologies (RWT), which completed an innovative robot demonstration project integrating a Cognex checkpoint 900 vision system with a 'universal robot controller' to perform online inspection of production parts for a leading automotive supplier. Various sizes of round holes and slots are punched on the workpiece. Screws are then used to connect to body parts through these holes; various wires and cables are led out through these holes. The punching process is done using hardware automation. Sometimes, due to tool breakage or wear, the punched holes are incomplete, or due to fixture problems, the punched holes are misaligned. Sometimes, due to tool wear, the hole dimensions are out of tolerance. Like most automotive suppliers, this leading automotive parts distributor aims for zero-defect parts. Besides process modifications, another way to ensure zero defects is through online inspection of the workpieces. To achieve maximum system flexibility, the video camera and light fixture are mounted directly on a tool holder at the end of the robot arm. The robot arm moves the video camera along the length of the chassis, scanning holes in the chassis. Simultaneously, vision software calculates the presence, size, and position of programmed holes. The operator can adjust the measurement specifications to ensure critical holes are within specified tolerances and avoid rejecting parts with non-critical holes that deviate. In practical applications, a two-second cycle can inspect 19 holes. This demonstration project also validated another manufacturing approach: effectively equipping existing robots with modern, advanced technology through a "brain transplant," and the feasibility of repositioning existing robots by upgrading them with a PC-based universal robot controller. At this leading automotive parts supplier, robots are typically decommissioned at the end of production runs for a particular model. Now, these robots can be repositioned with minimal capital expenditure in upstream processes such as online inspection. The demonstration project used a 15-year-old ABB IRB-6 robot, retrofitted with a 'universal robot controller'. The leading automotive parts supplier's plant, which implemented this demonstration project, houses hundreds of robots. At another top-tier automotive parts supplier, a Fanuc S-300 robot was retrofitted using a universal robot controller (UCC) on a "plug-and-play" basis. Within this production unit, the robot is used for loading and unloading materials during the punching of automotive seat frames. The URC retrofit not only involved a "brain transplant" of the Fanuc S-300 robot but also its integration with the punch press and other peripheral equipment. The entire retrofit, including reprogramming, was completed in less than two days. Conclusion Over the past 25 years, manufacturers have made significant efforts to develop and implement new technologies and processes to improve processes; increase production volume; offer a wider variety of products and bring them to market with shorter production cycles; improve quality; and reduce costs. Faster, better, cheaper. Generally speaking, industry has achieved remarkable success in these areas. However, cost savings from products may no longer be a viable method for cost reduction. Cost savings from processes are also not a good approach. In fact, improving the year-end profit and loss figures is the wiser choice. More attention should be paid to capital investment and extending the useful life of available control platforms. PC-based open architecture controllers may hold a crucial key to gaining a competitive edge in the next century. This key will be simplicity and standardization. PC-based control platforms possess all the "right qualities" to help manufacturers achieve their competitive goals in the 21st century.