Although contour navigation is the most commonly used system, some look at it as a bridge technology as LiDAR (Light Detection and Ranging) systems develop and come down in cost.
LiDAR is a laser-based technology that produces a two-dimensional view of the facility, measuring the building structure by identifying features such as columns, walls and racking. More than 50,000 data points are collected every two seconds, says Yale’s Micheletto. The technology can be used to manage a single vehicle or an entire fleet, he adds.
Mapping with a LIDAR vehicle is accomplished as with contour mapping. Similarly, SLAM processes the data and develops a map to guide the vehicle on its route. “The vehicle has its own map of the facility and makes its own decisions on the route to follow to its destination,” says John Hayes, vice president sales and marketing for logistics at Vecna Robotics.
In fact, LiDAR is catching on as this story is being written. Daifuku is the latest to offer it on autonomous lift trucks in the fourth quarter, says Bruce Busher, vice president sales for the company’s smart handling business division.
The third of these systems is a stereo camera-based system. This system from Seegrid enables self-driving pallet trucks and tow tractors.
The technology uses five pairs of cameras on top of the vehicle chassis, creating 360-degree view of the vehicle’s surroundings. Every quarter second the system collects millions of data points from the five cameras. The data is processed on board, providing a detailed, data-dense map of what is where on the vehicle’s route to ensure reliable navigation in dynamic environments.
What to watch for
So the question remains: What guidance system is best for your application? This is a process that requires active research on your part.
Established technologies continue to be just that. And, they are primarily focused on moving along pre-determined paths.
For the three new technologies, the predetermined path scenario is not as important as how the vehicle gets there, says Wise of Fetch Robotics—and in that may lay some of your most important decisions.
There are at least three important considerations to take into account when conducting your evaluation, say Savant’s Koff, Daifuku’s Busher and Vecna’s Hayes.
All emphasize the importance of managing fleet traffic and system integration. In other words, it’s not enough that a vehicle can make its own decisions and plot its own route. In a fleet, there are multiple vehicles to manage at any point in time. The challenge is to coordinate all of the vehicle routes not just so they don’t run into each other, but so they also get to their destinations in a timely, repeatable manner.
There is also a concern for the safety perspective, especially safety of people on the floor. Some AMRs meet the same ANSI B56.5 safety standards that AGVs do. Some don’t. In fact, some AMR suppliers say that because they are not AGVs, their vehicles do not have to comply. System evaluations should evaluate the importance of this factor in your facility.
And, of course, there is the matter of highly repeatable delivery of loads to a destination with great accuracy. Some of the systems available today require human intervention to complete the delivery. Is that a viable scenario given your level of floor activity in a given day? Only you can make that decision.
By all measures, this is a new age for navigation of AGVs and other autonomous vehicles. It’s opening up new possibilities on busy distribution and manufacturing floors. It’s also a transitional time as suppliers work out the details of how systems operate at all levels. That said, now is your opportunity to think of what’s most advantageous to decide what fits your future.