What makes up electronic control systems on mobile equipment?

 In Blog, Documentary

What makes up electronic control systems on mobile equipment?

Mobile equipment can vary, from equipment harvesting crops, spraying concrete in mines far underground, building highways to extracting oil from the ground. Although the equipment can vary greatly, most mobile electronic systems have the same basic components. This article reviews those components and how they fit together to successfully control the mobile equipment.

Microcontrollers act as the “brain” of the equipment, accepting inputs and sending output signals. They are similar to a PLC (programmable logic controller) used in industrial applications because they are the devices programmed to coordinate messages and movement – but with some differences. Microcontrollers are often used in mobile applications because they excel at working in the harshest environments. They also do well in larger mobile systems requiring several amount of Inputs and Outputs for an easier setup in a distributed control system. This makes installation and troubleshooting simpler and faster. They often use proprietary software languages (depending on the manufacturer) which require skillful programming. Choosing the right controllers is a key decision point for design of mobile control systems.

Human Machine Interface (HMI)

HMI are the screens (often touchscreens) where the operator of the equipment will interface with the controls, receive alarms about equipment operating outside normal parameters and log data to track and record machine performance. When designing a control system, it is critical to consider the operator and the skills needed to run the equipment. What can be done with the HMI to make it easier for the operator? When should the machine alert the operator of heat or high pressures before malfunctioning? How can experts remotely diagnose issues with the equipment? The remote-control HMI (wireless controls) has become increasingly popular to improve operator safety and/or decrease the manpower needed to operate equipment.

Inputs come from switches, buttons and sensors on the equipment. These inputs travel back to the microcontroller and depending on programming logic, impact outputs to control other components of the system. Outputs can be discrete signals, meaning simple on/off controls used to control equipment, such as basic directional control valves. Pulse width modulation is another type of digital signal which uses a duty cycle and frequency to control analog outputs such as proportional valves and motors.

Finally, networks hold the whole system together by transferring data between the operator and mechanical components. A large variety of network protocol exist and they continue to be further developed including profibus, modbus and ethernet. However, in mobile applications the vast majority of systems use a Controller Area Network or CAN to exchange data between microcontrollers, HMIs or other devices on the network. Since its inception, CAN has been the preferred network for mobile applications because it works well with truck engines using the J1939 protocol, and provides significant robustness and reliability.

Within these basic components, millions of options exist for designing systems for all types of applications. From simple to complex, whether explosion proof or able to withstand harsh operating conditions, the right products and programming expertise should be considered to create a system designed for efficiency, precise control, and budget considerations in high torque or high speed applications. Contact Elite Controls for the expertise to design your next system.