In order to perform their tasks efficiently, automated material handling (AMH) systems, such as AS/RS and AGV, need the flexibility to move around on their designated paths in a factory without obstruction while maintaining constant communication with the control center through a wireless network. Additionally, the control center needs a reliable wireless network to monitor and control the AS/RS and AGV systems as well as sufficient bandwidth to send data and instructions to the systems and receive data, including live video recordings from IP cameras installed in these systems.
Select the Right Wireless Technology
When choosing a wireless technology for your AS/RS or AGV applications, in addition to the costs, you must consider the range, speed, deployment complexity, and spectrum usage requirements for your application. In a typical factory warehouse setup, aisles can be spread over a few hundred meters with mobile vehicles moving rapidly on these paths to retrieve or store goods. WLAN technology is best suited for your AS/RS and AGV applications as it provides sufficient range and can operate in the 5 GHz frequency. However, you must plan your wireless network and continuously optimize it for mobile operations to derive the maximum benefit.
Tip 1: Plan before Deploying Your Wireless Solution
As the wireless medium is invisible and operates over a frequency spectrum, it is crucial that proper analysis of the radio frequency spectrum is done to ensure that wireless communication takes place over a relatively clean environment with sufficient signal coverage. Not placing access points (APs) at the right locations to provide sufficient coverage, using the wrong antenna type, and failure to mitigate interference are some common issues seen in an unplanned network. Be sure to undertake a comprehensive site survey and planning exercise to ensure that the wireless network can meet your application requirements.
Tip 2: Validate Your Network Plan
Once planning is done, the next step is to use wireless equipment to validate the design. Start with a small area and test your network plan. You can use wireless sniffer tools within the area to trace various Wi-Fi spots to map out the actual profile of your network plan’s radio coverage. Selecting the right antenna, as well as installing it with the right mounting angle, is the key to ensuring that there are no blind spots in the path of the moving vehicles, thus avoiding breaks in communication.
Tip 3: Deploy Antennas Correctly
Selecting the right antenna type for your APs and clients installed on moving vehicles is a key factor in building a stable Wi-Fi network. For APs, you can select between ceiling antennas, panel antennas, or di-pole omni-directional antennas, depending on where you want to install your APs. In the case of client devices installed on AS/RS shuttles and AGVs, you can choose between antennas that can be installed on top of the vehicles or on the sides. Be sure to have sufficient overlap between APs so that communication performance is as uniform as possible.
Tip 4: Fine-Tune Your Network Parameters for Reliability in Mobile Conditions
Once wireless infrastructure deployment is complete, further fine-tuning of the radios is required in order to optimize communication reliability and ensure that the client radios on an AGV can roam smoothly among the APs without data loss, which could result in system downtime.
Tip 5: Consider the Impact of Harsh Environmental Conditions
For a wireless system to perform at its best, you must mitigate the effects of the operating environment and ensure that the electrical parts in your equipment can function without interference. Some AGVs operate under harsh environmental conditions, such as in a cold-storage warehouse where electrical equipment needs to be able to operate at sub-zero temperatures.
Another potential environmental hazard is the stability of the power motors on the AGVs. The power supply on the AGVs may not be capable of reliably providing steady current to the radio equipment with the best grounding paths. Therefore, it is essential that you use isolation protection at the power input and possibly on the antenna ports, as electrical interference can damage the mobile radios.
To learn more, download the AS/RS and AGV white paper.