Based on precision force control, we create a full range of actuator products to expand intelligence and seize the high ground

Affected by the epidemic, tense international relations and other factors, the growth rate of the intelligent manufacturing industry slowed down in the first half of 2022, but some companies also saw a rise against the trend, and Zengguang Intelligence is one of them.

It is understood that Zengguang Intelligence was established in 2018 and is a domestic manufacturer of precision force control actuators. Based on its independent core motion control algorithms, electronic circuits, software design and high-precision force control technology, its self-developed and produced electric grippers, electric push rods, electric slides, rotary cylinders and other actuator products have the characteristics of high intelligence, high flexibility and high precision. They are widely adapted to the precision manufacturing needs of high-tech industries such as 3C electronics, automobiles, and medical care, and have successively won the recognition and support of more than 1,000 customers including BYD, Foxconn, HuaDa Manufacturing, and Lingyi Intelligent Manufacturing.

In the first half of 2022, the performance of Zengguang Intelligent increased year-on-year. Various products such as electric grippers, push rods, slides, direct-drive actuators, servo controllers, etc. were mass-applied in 3C electronics, automobile and other industries. At the same time, medical scenarios also began mass production and batch shipments based on project verification in 2021. Among them, the high-end series of actuator products based on SoftForce® precision force control technology have received a warm response in the market, and more and more companies are beginning to seek to solve existing process problems through precision force control technology.

What are the reasons behind the rapid development of augmented intelligence? What is the significance and necessity of precision force control? How widely are actuators based on SoftForce® precision force control used? In this article, Gaogong Robotics had an in-depth discussion with Huang Anjie, founder and CEO of augmented intelligence, to get a glimpse of the truth.

With the disappearance of the demographic dividend, the sharp increase in labor costs, and the continuous outbreak of the epidemic, the "evolution" of the manufacturing industry to intelligent manufacturing is inevitable. For example, the implementation of robots in factories has solved the problem of whether there is a demographic dividend, but some processes and links of fine operations are still the application depression of intelligent manufacturing .

In order to solve the problem of limited application in precision scenes, companies have begun to try various methods. For example, various types of sensor products such as mechanical, optical, and tactile are installed on robots, and motion control algorithms are continuously optimized so that robots can meet the requirements of fine operations. However, it is always difficult to achieve both load, speed, and precision. Collaborative robots have force control functions by being equipped with six-dimensional force sensors, which can be used in grinding and assembly of large parts. However, if the force control is to be sufficiently precise to perform operations such as assembly of small components, its operation speed and precision may not meet production indicators.

Huang Anjie analyzed: " The widespread application of robots and actuators in various industries corresponds to the problem of "having" or "not having" productivity. The combination of robots and actuators with various sensor products corresponds to how to create excellent productivity." Without force sensors, there is no force feedback, and robots or actuators will not have any sensing functions. Actuators based on SoftForce® precision force control are different from common current loop or direct drive force control methods. They can achieve an excellent balance between load, speed, position accuracy and force control accuracy, expanding the application scenarios of actuators to more precise operation requirements. "

Specifically, there are two traditional force control methods . The first is current loop force control , which achieves force control by adjusting the current inside the motor. It is relatively easy to implement and can achieve force control within an accuracy range of 5%-15%, but the movement speed is slow, reverse transmission is not possible, and a smaller force cannot be achieved under load. It cannot meet the needs of some scenarios with higher precision requirements, and after a period of use, mechanical wear will cause errors and further reduce accuracy. Even if a direct drive method is used to reduce the friction of the transmission mechanism to obtain a more precise and tiny force, its minimum output will not be less than 0.3N. At the same time, this type of actuator usually does not have a sensor, and even if it does, it does not participate in control.

The other is sensor closed-loop force control , which adds conventional force sensors and conventional closed-loop control algorithms. The accuracy is improved compared to current loop force control, but the speed is still slow. In general, this method can increase the force control accuracy from 5% to 1%. However, without the correct algorithm processing or the sensor speed is not fast enough, it is easy to produce "overshoot", causing the force output to exceed the final steady-state value, which is directly manifested in the low final yield rate.

Compared with traditional force control, SoftForce® precision force control is fundamentally different in three aspects: "whether it is equipped with a sensor", "how high the control frequency is" and "whether the load will affect the output position and output size".

Taking augmented intelligence's precision force control technology as an example, combined with high-speed force sensors and model-based predictive control algorithms, SoftForce® 3.0 accurately controls torque through almost real-time force feedback. The actuator can automatically identify the actuator's position and contact status with the workpiece, giving the actuator the same force perception, control and execution intelligence as a human hand.

" The concept of 'digital twin' that everyone often talks about now is actually one of the specific implementation methods of our 'control algorithm based on model prediction'. Through complex motion data simulation modeling, we can achieve rapid self-learning and dynamic adjustment, thereby realizing precise and high-speed control and execution at the physical level ," Huang Anjie added, "We proposed and successfully implemented SoftForce® precision force control technology as early as 2019, which upgraded the electric actuator to a robot-like actuator with perceptual intelligence."

To date, Augmented Intelligence's SoftForce® precision force control technology has been upgraded to version 3.0, which allows the actuator to be faster, the force control to be more precise and accurate, and the whole process of force control to be achieved . It also has five major advantages :

1. High processing frequency and instantaneous force feedback to achieve better performance. It is reported that the calculation cycle of the common "six-axis force sensor + robot" force control solution on the market is about 5-10 milliseconds, and the processing frequency is 100-200Hz, while the processing frequency of the SoftForce® 3.0 precision force control actuator reaches 10,000Hz (that is, a closed-loop calculation is completed in 0.1 milliseconds), which is 50-100 times the processing frequency of general robot force control. (The processing frequency here refers to the closed-loop processing frequency of the control. In fact, the frequency and resolution accuracy of the force sensor used are much higher).

2. Highly flexible force control allows the actuator to respond instantly to external forces and achieve active flexible force control. Even if it encounters external forces during operation, it can be adjusted in time, making the process more precise and better protecting the workpiece.

3. High frequency and high speed without overshoot . Even under high frequency and high speed movement, it still maintains high output accuracy and ensures "no overshoot". It contacts the surface of parts with high speed and small force, performs flexible pick-and-place of parts, etc., to avoid damage to delicate and fragile parts.

4. Stronger overload resistance . Based on a deep understanding of the on-site process and multiple iterations, Zengguang's newly upgraded precision force control HF series in February this year has an integrated sensor design, which has an overload resistance that is 4-8 times higher than before, is more durable, and can easily cope with more complex working conditions.

5. It can take into account both micro-force and large-force output . The precision force-controlled slides and push rods with large stroke and large load equipped with SoftForce® 3.0 high-precision force control system can produce micro-force and precise force under high load, and can also produce large force at the same time, with a larger force output range, that is, a wider force dynamic range.

Talking about the overall advantages of precision force control , Huang Anjie said: "SoftForce® precision force control is an innovative control technology system, and it should be said that it is a manifestation of actuator application technology to another level. It makes it possible to replace human hands in processes or scenarios that were previously impossible with machines. Now, SoftForce® precision force control can achieve this."