The very simplest IIoT robotic devices are called actuators. Simply put, actuators cause something to happen. They can turn something on or off and even lock or unlock a door. Actuators can cause a motor to spin, move a robotic arm, install a bolt or a rivet. Multiple actuators can be chained together, sometimes all on the same machine, to perform a whole series of functions. Generally, actuators are triggered by a short signal. The amount of data transferred over a network to one of these devices is quite minimal, and the latency typically isn’t critical. This means that actuators are very easy to support on a Wi-Fi network.
Moving up the hierarchy of industrial robots, the next level of intelligence and functionality is represented by Computer Numeric Controllers (CNCs). These are programmable devices which depend upon their software to guide their operations. They are capable of complex processes, such as cutting intricate patterns into sheets of metal. Once programmed, CNCs tend to operate rather independently. However, they need Wi-Fi connectivity for programming, reporting, and management functions.
Next come Programmable Logic Controllers (PLCs). These are smart IIoT machines. They have actual CPUs that continuously monitor their processes and make decisions based upon that input. So, if a PLC is cutting the sheet metal mentioned above, it will be checking the precision of each cut, along with the thickness of the metal, and the integrity of the cutting blade. It will self-correct for any minor anomalies. PLCs are also capable of very complex assembly processes, like installing hundreds of electronic components on a tiny circuit board. All of these real-time processes require frequent communication with a central server. This means that the underlying Wi-Fi network must be highly available.
And finally, the most impressive robots on the factory floor are the automatic guided vehicles (AGVs). As the name implies, these are vehicles – typically used for materials handling or load carrying – that move autonomously throughout the factory without a driver. Think of them as self-driving cars. However, they won’t have the same level of onboard programming (or pricing!) as a Tesla. Instead, they need to communicate with a central controller whenever they are underway. AGVs will transmit and receive complex routing, collision avoidance, and logistical information, and they can even support video. Therefore, the Wi-Fi network must be designed to be highly available, provide plenty of bandwidth, and have very low latency.