What are the implications of an electronics assembly line designed to run without operators?
After two decades of talks about how Lean manufacturing is going to save the world, we are now a few years into two decades of Factory 4.0 and Smart Factory hype. Consultants and manufacturers of tape used to mark equipment location on the floor benefitted most from Lean manufacturing. Who will benefit most from Industry 4.0?
Labor costs have been the main reason behind the migration of electronics manufacturing plants. Automation, including robotics, was never a primary reason for loss of electronics manufacturing jobs, as often promoted. That is about to change. Although loss of jobs is completely avoided in all Industry 4.0 panels and discussions, it will happen. High-cost Western countries will promote total automation to be able to keep manufacturing plants at home and solve quality labor issues. The technological advancements cannot be stopped by not talking about them. Envisioning the future will prepare us for the future. New generations need to be trained to program robots, use artificial intelligence to solve problems, program mobile applications, and gain skills to work at the new high-tech companies.
Over time there will be fewer well-paid industrial jobs in electronics manufacturing. This article proposes the design of electronics assembly lines that could run without operators and be controlled by just a small number of skilled workers from a control room.
Printed circuit board assembly (PCBA) is a complex process that involves operators, machines, materials and processes. Current software, information systems and equipment are not designed to run a plant without operators. New solutions are necessary. Use of the following modern technologies is discussed here and proposed to support lights-out electronics assembly:
- Programmable logic controllers that support embedded applications and Internet of Things (IoT).
- Artificial intelligence (AI).
- New electronics assembly equipment designs.
- Machine-to-machine (M2M) communication standards.
- Robots and automated guided vehicles (AGVs).
- RF technology.
We will not consider cloud computing as a viable technology for lights-out electronics assembly. No serious manufacturing company will use cloud computing until its shortcomings are solved: security and cost. In the words of an Industry 4.0 manager in a large automotive electronics company, “With cloud computing, we still have to have database administrators and IT personnel, plus all security risks. No, we will not be using it anytime soon.”
We will also not discuss 3D printing, often included as an emerging technology in Industry 4.0 discussions. While 3D printing will reduce cost and production downtime by providing cheaper and easily available parts and devices, its contribution to lights-out electronics assembly is negligible.
A smart factory consists of smart subsystems of automation that communicate with other subsystems using a standard communication protocol. Intelligent subsystems must be able to perform their function unattended, while collecting all data needed to support business decisions. To achieve lights-out electronics assembly, the following concepts must be integrated into a smart factory design:
- Intelligent and real-time production control.
- Smart and reliable equipment.
- Smart products.
- Smart interfaces.
- Mobile solutions.
- Intelligent predictive equipment maintenance.
- Manufacturing intelligence.
In the following sections, the application of these technologies to electronics assembly is discussed. Finally, their integration in lights-out electronics assembly lines is proposed.
Intelligent Production Control
An interesting ongoing discussion in the Factory 4.0 community is about the future role of ERP and MES systems. Smart machines and smart products will make MES systems obsolete. On the other hand, ERP systems are actually a much bigger obstacle to the success of smart factories and the overall Industry 4.0 idea.
Developers of ERP systems are able to sell a big database, outdated algorithms and lousy interfaces for millions of dollars. ERP systems lure companies into believing they have everything in control just by implementing an ERP system. That is far from the truth.
Lights-out electronics assembly plants will be based on real customer demand. They will build quality products at a fast production rate. There is no place in smart factories for forecasting and the centralized, but often wrong, job progress tracking of today’s ERP system. In addition, lights-out electronics assembly plants will be able to produce batch sizes of one without production delays.
If we eliminate ERP and MES systems, how will some of the most important production decisions be made, including when to reorder components, what line to send the next job, when to send AGVs to bring bare boards, when to switch programs on machines, when to send AGVs to bring material replenishment, etc.?
The future is in smart assembly equipment and smart products interacting for real-time production scheduling, or as we call it, assembly line self-scheduling. The smart lines will know how many products have been completed of the current work order and will request the next job, as well as advise what kind of products the line can do. Smart products will compete for assembly line time based on their priority (due date or urgent delivery need), material availability and technological constraints. The assembly line self-scheduling process will be monitored using production scheduling dashboards in the control room.
The traditional MES function, WIP tracking, will be performed by smart products. Products will carry information about process operations and WIP status. Machines will talk to each other to change program, change conveyor width and other setup actions.
A central database will be used to store machine programs, release work order data, inventory counts, and other plant wide data. Components will be reordered based on actual demand and electronic Kanban signals sent to the supplier. A supplier-maintained inventory system will be used.
Smart equipment. Current electronics assembly equipment is not designed for smart factories. However, some equipment manufacturers are designing equipment that will support lights-out electronics assembly. Some will be discussed in this paper in the following sections.
The concept of smart equipment goes further than just simply changing machine design. Autonomous and smart machines and assembly lines are independent intelligent subsystems of automation that can talk to other equipment and smart products to control production, as well as to report and request their own maintenance needs. There are two stages in achieving smart equipment to support lights-out electronics assembly:
- Attach a “machine brain” to an existing machine (short term).
- Embed a machine brain into new equipment designs (long term).