The development of SMT placement machines has gone through several stages and new technological trends.

Since its inception in the early 1980s, the basic functionality of the pick-and-place machine has remained largely unchanged. However, the requirements for placement—particularly in terms of speed and precision—have undergone significant transformation due to the rapid development of the electronics industry, as well as the trend toward miniaturization of components and high-density assembly. We exclude from our discussion the so-called small-batch-level equipment, namely manual SMT placement machines, which were used in the early days and are still used today primarily for product prototyping and research. This is because these machines cannot compete with mainstream SMT placement machines in terms of technical level and application scope. Regarding mainstream SMT placement machines used for mass production, they can be categorized into three generations from a technical perspective. Let us first introduce the development stages of SMT placement machines and new technological trends. 

First, we want to discuss the developmental stages of SMT pick and place machines. The earliest equipment in the SMT industry was the first-generation pick-and-place machine. The first-generation pick-and-place machine emerged in the early 1970s to the early 1980s as an early assembly device driven by the application of surface mount technology in industrial and consumer electronics. Although the mechanical alignment method used in those pick-and-place machines resulted in low placement speeds of approximately 1,000 to 2,000 components per hour and relatively low placement accuracy, approximately ±0.1 mm for X-Y positioning and ±0.25 mm for placement precision, and despite their simple functionality, they already possessed all the essential elements of modern pick-and-place machines.

Compared to manual component insertion assembly, such speeds and accuracy represented a profound technological revolution. Furthermore, the first-generation SMT placement machine ushered in a new era of large-scale, fully automated, high-efficiency, and high-quality production of electronic products. For the early stages of SMT development, when surface-mount components were relatively large, such as chip components of the type 1608 and IC pitch ranging from 1.27 to 0.8 mm, these machines were already capable of meeting mass production requirements. With the continuous development of SMT and the miniaturization of components, this generation of SMT machines has long since been phased out of the market and is now only found in a few small enterprises. The next development was the second-generation pick-and-place machine. From the mid-1980s to the late 1990s, the SMT industry gradually matured and developed rapidly. Driven by this growth, the second-generation pick-and-place machine built upon the first-generation model by adopting an optical system for component alignment, significantly enhancing the machine’s speed and precision. This advancement met the growing demand for the rapid proliferation and development of electronic products. During this development process, two distinct types of machines emerged: high-speed machines primarily designed for mounting chip components and emphasizing mounting speed, and multifunctional machines primarily designed for mounting various ICs and irregularly shaped components. These two types of machines have clearly different functions and applications. 

The second-generation pick-and-place machine also has two subcategories, the first being high-speed machines. High-speed machines primarily use a rotary multi-head, multi-nozzle pick-and-place head structure. Based on the rotation direction relative to the PCB plane, they can be further classified into turret-type (where the rotation direction is parallel to the PCB plane) and wheel-type (where the rotation direction is perpendicular or at a 45° angle to the PCB plane). Thanks to the adoption of optical positioning alignment technology and precision mechanical systems, such as ball screws, linear guides, linear motors, harmonic drives, precision vacuum systems, various sensors, and computer control technology, the placement speed of high-speed machines has reached the order of 0.06 seconds per piece, approaching the limits of electromechanical systems. The second branch is the multi-functional machine. Multi-functional placement machines, also known as universal machines, can place various IC packaging components and irregularly shaped components, as well as small chip components. They can accommodate components of various sizes and shapes, hence the name multi-functional placement machine. The structure of multi-functional placement machines mostly adopts an arch-type structure and a linear motion multi-nozzle placement head, featuring high precision and good flexibility. Multi-functional machines emphasize functionality and precision, but their placement speed is not as fast as that of high-speed placement machines. They are primarily used for placing various packaged ICs and large, irregularly shaped components, and are also used for placing small surface-mount components in medium and small-scale production and prototyping.

With the rapid development of SMT and the further miniaturization of components, the emergence of more refined SMD packaging forms such as SOP, SOJ, PLCC, QFP, and BGA has made this generation of pick-and-place machines increasingly inadequate. They have gradually faded from the mainstream of pick-and-place machine manufacturers’ focus. However, a large number of second-generation pick-and-place machines are still in use today, and their application and maintenance remain important topics in SMT equipment.

The main technical features of the 3rd generation pick-and-place machine generally include a modular composite architecture platform, high-precision vision system and flying alignment, dual-track structure, multi-arch, multi-pick-and-place head, and multi-nozzle structure, intelligent feeding and detection, high-speed, high-precision linear motor drive, high-speed, flexible, intelligent pick-and-place head, and finally precise control of Z-axis movement and placement force. While technology is one aspect, the primary characteristics of the 3rd generation pick-and-place machine lie in its high performance and flexibility. For example, it combines the functions of a high-speed machine and a multi-functional machine into one. Through the flexible structure of modular/module-based/cell-type machines, different structural units can be selected to achieve the functions of both high-speed and general-purpose machines on a single machine. Balancing placement speed and accuracy is also crucial. For instance, the new-generation placement machine employs high-performance placement heads, precise visual alignment, and high-performance computer hardware/software systems.

Additionally, high-efficiency placement is achieved through technologies such as high-performance placement heads and intelligent feeders, enabling the machine’s actual placement efficiency to reach over 83% of the ideal value. High-quality placement is also critical. This is achieved through precise measurement of Z-axis dimensions and control of placement force to ensure good contact between components and solder paste, or by applying APC to control placement position, thereby ensuring excellent焊接 results. Overall, the production capacity per unit floor area of third-generation placement machines is approximately twice that of second-generation machines. Finally, the third-generation pick-and-place machine can also implement intelligent software systems for stacked assembly. This is one of the reasons why the third-generation pick-and-place machine is currently developing so rapidly.

Second, we want to discuss the future prospect and development of the third generation SMT pick and place machines. First and foremost is high performance: in the development of pick-and-place machines, speed, precision, and placement functionality have always been in a state of conflicting priorities, forcing users to compromise between speed and precision. As a result, high-speed machines and multi-functional machines remain the two primary placement modes in use today. However, in the increasingly competitive landscape of future electronics, where product updates are accelerating and the trend toward diverse product varieties and small-batch production is becoming mainstream, new packaging technologies such as BGA, FC, CSP, and PoP are placing ever-higher demands on SMT machines. As a result, SMT machine configurations must evolve to keep pace with these changes. With the development of SMT machine technologies such as modularization, dual-lane conveyance, multi-arm, multi-placement head structures, flying alignment, and lightning placement, achieving a balance between speed, precision, and placement functionality within a single SMT machine has become the new direction.

High-performance SMT machines that integrate high speed, high precision, multi-functionality, and intelligence will become the mainstream; The second point is high efficiency: high efficiency means improving production efficiency, reducing working hours, and increasing production capacity. For automated CNC equipment such as pick-and-place machines, software programming efficiency is crucial to improving equipment efficiency. Developing more powerful software functional systems, including various forms of PCB files, directly optimizing the generation of pick-and-place program files, reducing manual programming time, developing machine fault diagnosis systems, and comprehensive management systems for mass production, and achieving intelligent operation are key components in the future development of high-efficiency pick-and-place machines. Additionally, improvements in equipment structure and operational modes are also important methods for enhancing production efficiency. Dual-lane conveying SMT placement machines retain the performance of traditional single-lane machines while designing PCB conveying, positioning, inspection, and placement into a dual-lane structure. This dual-lane structure can operate in either synchronous or asynchronous modes, both of which reduce the machine’s idle time and enhance production efficiency; The third point is high integration. High integration refers to two aspects: the integration of equipment technology and the integration of technology and management. The integration of equipment technology involves the cross-application, integration, and fusion of multiple technologies. For example, mechatronics integrates detection and sensing technology, information processing technology, automatic control technology, servo drive technology, precision mechanical technology, and system-level technology into a comprehensive application.

Regarding the integration of technology and management, it involves fully leveraging computer, automation, and network technologies to achieve the organic integration of equipment application and management technologies. The utilization of integrated equipment, such as automated production lines, is particularly important. For instance, embedding SPC and traceability systems into SMT production line equipment can maximize equipment performance, enhance production capacity, and improve quality; The fourth point is the use of green energy. It is an inevitable trend in the future development of electronic manufacturing. The development of human society will inevitably lead to harmony between humans and nature, and pick-and-place machines are no exception. In the future, pick-and-place equipment must consider environmental impact from the conceptualization stage through design, manufacturing, sales, use and maintenance, recycling, and remanufacturing stages, with a focus on improving material utilization, reducing energy consumption, and maximizing user investment returns. In recent years, the concepts of green manufacturing and environmental protection have taken on new meanings. Environmental protection is now understood in a broader sense, encompassing not only the protection of the natural environment but also the social environment, the production environment, and the physical and mental health of producers. Under these circumstances, the goal is to develop high-precision, high-efficiency, high-quality placement equipment with short delivery times and excellent after-sales service; Finally, the most important factor is diversity. The world today is a diverse and multifaceted place. Development is uneven across different countries and regions, and even within the same country, different regions develop at different paces. This leads to diverse demands for the quality and grade of electronic products.

At the same time, different application areas have vastly different requirements for the reliability of electronic product application environments, which also drives diverse demands for product manufacturing processes and equipment. This diverse demand will drive the future development of assembly equipment toward a diversified structure and cross-disciplinary technologies. On one hand, manufacturers will need to accommodate both multifunctional, flexible universal pick-and-place machines capable of handling multiple product types and high-efficiency specialized pick-and-place machines tailored for specific fields and products.

To conclude, there will be a need to produce high-end pick-and-place machines featuring full automation, intelligence, high precision, and high production capacity to serve large enterprises and high-density assembly requirements, as well as mid-to-low-end pick-and-place machines suitable for small and medium-sized enterprises and general electronic product needs. This approach allows for the concurrent development of high-performance mainstream SMT machines tailored for large-scale industrial manufacturing and smaller, non-mainstream SMT machines suited for research, education, and laboratory applications.