Learn about mobile robots from scratch (V) (How to choose the controller type)

It is the most important core component of mobile (AGV/AMR) and the "brain" of the entire vehicle body, which is related to the reliability, stability, performance indicators and safety of the vehicle body. It is usually used to receive data collected by the module, and perform information processing and analysis to issue various motion instructions. At present, the mobile robot controller mainly controls the robot's movement position, posture and trajectory in the workspace, operation sequence and action time, etc.

1. Controller Type

The importance of controllers in mobile robots is self-evident. They control and manage all activities of the robot. It can be said that a good controller can improve the performance, reliability and safety of the robot and add more functions for different application scenarios. At present, we basically divide the on-board controllers used by AGV/AMR into the following four types:

： It is a programmable controller, which is a special digital controller. Its main functions are to perform discrete input and output, logical operations, data acquisition and control execution, etc. However, the programmability of PLC is relatively limited. Only PLC-specific programming languages ​​can be used for program development and configuration. Although control and operation functions can be realized, the accuracy and speed are relatively limited.

Industrial computer (IPC): a computer with important computer attributes and characteristics. Its main functions are data processing, image processing, control algorithms, etc. It is widely used in complex systems. There is no difference between the operation of industrial computers and general computers, which places high demands on the quality of operators. In addition, once an industrial computer system fails, it is difficult to diagnose the faulty component, and the price is moderate.

(MCN): refers to a complete computer system integrated on one piece. They are small, low cost and easy to program, however, all components of the MCU are not industrial grade, the anti-interference ability is especially weak, and the development requires a high level of expertise as well as investment of time and resources.

The applications of the above three are not clear-cut. For example, the internal core of PLC is a single-chip microcomputer; the programming language of industrial computers may also adopt the ladder diagram and other languages ​​commonly used in PLC; embedded real-time can also be loaded on the single-chip microcomputer to form a powerful multi-tasking computer. Therefore, although each has its own applicable fields, they will also learn from each other and integrate applications. With the continuous development of AGV/AMR technology, navigation methods have become more and more diversified, and the application of new technologies such as laser and vision has greatly increased the computing power requirements of the controller, which has also given rise to the birth of dedicated controllers for mobile robots.

Mobile robot dedicated controller: It is a controller specially designed for mobile robots, integrating mature navigation and motion control (such as laser positioning algorithm, Mecanum wheel control algorithm), with low power consumption, fast response speed, strong anti-interference ability, etc., which can better meet the needs of the mobile robot industry. In addition, its modular design also provides users with more customizable options to adapt to various application scenarios.

The AGV/AMR controller is the core of the AGV/AMR control system. Developing a dedicated AGV/AMR vehicle-mounted controller based on an embedded computer system to replace the AGV/AMR vehicle-mounted controller that uses an industrial computer or a general PLC as the main control unit is the future technology development trend and the focus of future research and development work.

Choosing the right controller is a crucial part of the robot system. Different types of controllers can be selected according to the application scenarios and functional requirements of the robot. So how do you choose a controller that suits you?

2Core factors for selecting a controller

Generally speaking, choosing a good one requires multiple dimensions. When choosing a controller, in addition to performance, you also need to consider product functional applications. Only by choosing a suitable controller can you ensure the stability and reliability of the robot system and improve the performance and efficiency of the robot system.

In terms of performance, the controller needs to have certain hardware, embedded, algorithm and system-level indicators and to ensure its reliability and stability, including temperature range (-40～80)℃, relative humidity range (10～90)% RH, IP protection level IP54 or above, explosion-proof certification, corrosive gas environment level, etc. As well as the speed, accuracy, stability and response time that can be achieved. In addition, the controller also needs to have redundant technical indicator capabilities to ensure long-term, continuous, reliable and stable operation.

In terms of functional applications, the controller should be able to adapt to different navigation methods and chassis types according to its own needs, and at the same time have a certain degree of openness to support users to carry out secondary development according to actual application needs. Different types of controllers have different functions, so you need to choose according to specific needs. For example, some controllers may support SLAM technology (simultaneous positioning and mapping), while others may not.

Nowadays, in the field of modern logistics, dedicated controllers for mobile robots have become an indispensable part, making great contributions to enhancing productivity and reducing labor costs. In order to better adapt your own robots, using professional mobile robot controllers allows you to focus on the project itself without having to spend too much energy on the underlying hardware and software, thereby improving R&D efficiency and success rate. Turn the fixed R&D cost and uncontrollable time cost into a controllable cost. You will have more energy to focus on the end-user's application solutions, process flows, etc.

Choosing the right controller depends on factors such as the required functions, budget, and familiarity with the development environment. However, ensuring the stability and reliability of the controller is also very critical, which will directly affect the performance and working effect of the robot. A professional controller for mobile robots is a better choice.