There’s a sense that the global economy is changing at an increasing rate. Almost overnight, markets can dry up, products can require a redesign, and technologies can advance. There’s a strong demand in manufacturing for systems that can respond quickly to those changes. With pits, chains and miles of metal track, traditional conveyance doesn’t offer flexibility in paths, processes, or products.

AGVs provide flexibility in all three types of change:

  • Paths: Whether through inductive power transfer, magnetic tape, or geolocation, AGV paths are quickly changed. There are typically few monuments involved, even for very heavy and complex products.
  • Processes: If the AGVs have an onboard PLC, they can be reprogrammed to respond to process changes by spending less time in station, advancing asynchronously, requiring process completion for advancement, and more.
  • Products: AGVs create a moving surface with power for onboard lift and rotation. By including quick-change clamping mechanisms, positioning fixtures, and tool attachments, one AGV can handle a variety of products.

For years, AGVs weren’t considered practical for manufacturing because of unpredictable battery life, but today there are alternative power sources that make AGVs a true 24/7 conveyance option.

Product launches often entail some type of ramp-up, with limited initial production preceding full throughput rates. With traditional chain-based conveyance, manufacturers essentially have to buy all the conveyance they’ll ever need, before they really need it. It’s generally not practical to install part of an overhead power and free track, or just a few skillets. Instead, they have to make the full conveyance investment at the start of the project, even if they won’t be up to capacity for some time.

AGVs allow a staged investment. Companies can buy only the number of AGVs they need for initial launch, adding AGVs as they increase production rates. This approach reduces capital outlay, lowers risk, and better aligns production expense with revenue.

We live in a world of product customization, and customers have high expectations about product variety and improvements. Multi-model production is more and more the norm.

Conveyance that’s designed around a single product or set of products is inherently expensive to change. We’ve seen that for decades in automotive manufacturing, as most automakers scrap thousands of pounds of conveyor metal for every major model change.

Since they’re not physically attached to the building, AGVs are more suitable for multi-model and periodically changing assembly lines. Automated guided vehicles can be refixtured, relocated, and reprogrammed to handle a variety of products.

Asynchronously indexing AGV assembly line
Asynchronously indexing AGV assembly line (Source: Manufacturing Tomorrow)

There’s no stopping the forward motion of automation in manufacturing. At the same time, not everyone wants or can afford a line of robots for every assembly line. AGVs offer automation that supports and protects the operator, with ergonomic lifts and product positioning, configurable safety zones to eliminate collisions, removal of trip hazards, and a quieter work environment that facilitates better communication between workers.

In a traditional conveyance world, chains and plates and miles of metal dominate the assembly line. With AGVs, software and controls play the primary role. With onboard PLCs, AGVs can interact directly with a manufacturing execution system, allowing the integration of error proofing, traceability, part kitting, and more. The AGV becomes an intelligent component of the entire system, with the ability to engage with the plant MES, rather than a “dumb” mechanical chain device.

>> Read more by Mark Sobkow, Manufacturing Tomorrow, 2/23/17

What’s Driving Assembly Line AGVs?