By Rob Sullivan, president and CEO, AutoGuide Mobile Robots
With forklifts an ongoing contributor to workplace accidents, and skilled operators difficult to find and retain in today’s competitive manufacturing environment, automating material transport is solving both issues.
A few years ago, a top-tier automotive manufacturer wanted to reduce how often employees had to manually lift and move heavy objects, and eliminate the risk of forklift-related injuries.
They understood that they needed safer and more efficient solutions for transporting engines and other materials from assembly to testing within their 40,000 square foot facility.
At first, the company’s global “fork-free” safety initiative prompted a switch to manually-driven tow tractors with automatic trailers for this lineside tugging task.
Unfortunately, not only were high-value employees still tied to low-value transportation tasks, but they had to tug more trailers in a single trip than they could safely maneuver in an ever-changing manufacturing facility.
Consequently, management went back to the drawing board to find an automated approach that better addressed safety and labor concerns.
Deployed within weeks, the AMR tuggers with custom trailers integrated with manufacturing conveyors to deliver lineside supplies on a just-in-time basis. When inventory on a conveyor reaches a predefined level, sensors alert the robot’s fleet control software to dispatch the tugger to refill the supply.
Once the tugger arrives at the consumption point, the software notifies the automatic trailers to deliver materials to the conveyor and load empty containers back onto the trailers via their own powered conveyor system. Once the exchange is complete, the software dispatches the vehicle back to the pickup point.
Automatic trailers and conveyors then exchange empty containers for full containers and the autonomous tugger is sent to a charging location where it waits for the next low-parts signal. In one trip, a single AMR tugger can carry what typically takes two manned forklift trips to transport, which adds up substantially over the course of a typical day.
This manufacturer was able to move four team members (two workers in two shifts) to higher value tasks, while maintaining just-in-time lineside supply delivery and their 95% uptime goal.
The AMR tugger also improved safety risks the manual drivers faced, including long trailers, visibility issues for drivers and narrow pathways. ROI came in 12 months when considering the cost of the AMR itself, with a 22-month ROI on the cost of the entire project, which included integrator-provided automated trailers and conveyor retrofits.
What to Look for in an AMR
While an AMRs’ ability to independently move around a facility without the need for disruptive and expensive infrastructure is universal, AMRs are not all the same. To make sure you’re getting the best one for your organization, ask the following questions:
1. How safe are your mobile robots?
The safest AMRs include floor-level sensors and LiDAR scanners that detect objects and personnel in their path and react accordingly, dramatically reducing the risk of accidents.
This automotive manufacturer added vertical load sensors that sense obstacles or traffic for the full length of the load extending in front and to the sides of the vehicle.
This allows the AMR to safely operate in congested spaces and maneuver around other traffic while still taking advantage of the flexibility and speed of the AMR tugger.
To ensure worker safety, the manufacturer also integrated the robots’ fleet control software with multiple external devices such as traffic lights and emergency response systems so that workers in the area were constantly aware of the vehicles’ movement.
In addition, because AMRs can transport multiple pallets in a single trip, they require fewer trips to move the same or more materials as manned forklifts. Fewer vehicles on the floor interacting with other equipment and people naturally lowers the likelihood of accidents.
AMRs also reduce the risk of accidents caused by unfocused operators that might run into obstacles, including people, in their path.
To truly feel comfortable that the robots you are considering are safe, however, ask the vendor which safety standards they follow.
There are currently two main standards manufacturers look to as they design their robots – ANSI B56.5 (US) and EN1525 (EU), but both were created for automated guided vehicles (AGVs), which travel on fixed paths guided by wires or magnets embedded in the facility.
To address AMRs specifically, the Robotics Industries Association (RIA) published the first part of its new ANSI/RIA R15.08 aimed at increasing the safety of employees that work alongside AMRs.
2. How quickly can the robots be deployed?
With its ease-of-use and quick training, the deployment of AMRs should typically take weeks, rather than the months it would take if tape or magnets needed to be installed into the floor to deploy an AGV, for example.
Once this automotive manufacturer prepped their facility, it took only eight days for the AMR tugger to be up and running, including mapping the entire environment, teaching the AMRs all the routes, and optimizing the system.
When routes are reconfigured in response to production changes, there is no need to reteach the entire facility, just the areas added or changed.
3. How adaptable are the AMRs if my needs change?
The most efficient – and advanced – AMRs are designed with flexibility in mind, ensuring the systems can meet manufacturing and lean principles.
An architecture based on a standard base AMR with modules or adapters that transform the base unit into a tugger like this manufacturer used, or even a pallet stacker, maximizes your investment.
When requirements and plant layouts change, the adapters can be changed as well, enabling the robot to perform new tasks. A well-designed AMR is easily extendable and changeable, without the need for facility modifications.
4. How easy are they to integrate with existing environments and other automation applications?
The AMRs’ fleet control software should manage the AMR tuggers’ orders and missions, and coordinate their activities to minimize empty travel.
In addition to optimizing routing and traffic so congestion is limited, the software should be able to integrate with existing warehouse management systems (WMS), delivering an integrated solution that simplifies operations.
They should also be collaborative, able to safely work alongside other robots and people.
5. Are your AMRs designed as an AMR or converted from manually operated vehicles?
Bolting automation kits onto existing, manually operated machines is not ideal, but it’s how some AMRs are built. A purpose-built AMR ensures the robot is optimized for autonomous operations because each component – from motor, wheels, control systems, sensors, safety system, and central computer – is engineered to work together as a high-performance material transport robot.
Finding the right AMR solution to drive your lineside tugging tasks and other material transportation workflows not only results in improved productivity and increased safety, but also has a positive impact on your operation’s profitability.
The benefits of deploying AMR tuggers for this one task within one location has prompted the manufacturer to deploy AMRs for other workflows within the same facility and extend autonomous solutions to additional facilities, including automating the movement of heavy car frames from paint to final assembly. Read more about that one here.