Control Engineering

Paul Grayson

Packing The Truck
November 9, 2007

NEW AREA AUTOMATED

The hot new area of AGV automation is kown as the "last 60 feet."  That is the distance between the end of the automation in an otherwise fully automated manufacturing plant and the truck waiting at the loading dock.  Attempts in the past at automating this final leg of the manufacturing and distribution process were hampered by the uncontrollable variables of the semi-truck trailer: height, width, out of square, misalignment with the dock, lack of navigation markings and many other variables.  Trying to incorporate the trailer to be loaded as an extension of the AGV's route in the plant was also hampered by the computer processing power and sensors available.  Recent advances in computers and sensors have made it possible now to automate the "last 60 feet" and the less well know "first 60 feet" - the unloading of trucks delivering materials as they arrive at the plant to begin their trip through the automated manufacturing process. 


Sky-lighted semi-truck trailer sealed against the loading dock, 
being loaded by an AGV side-shift-fork forklift truck.

Everything in the USA moves by truck.  Even things that are shipped part way by air or railroad start and finish their journey by truck. Automating the loading and unloading of trucks is where that AGV action is.  Leasing agreements have moved the use of AGV's from a capitol investment to an employment cost.  This change in accounting for the cost of AGV use has made the return on investment immediate and cash positive from the start.  Manufacturers who have already hired AGV's to work in their plant know firsthand the savings that can be made and are the first ones asking to have this new leg of AGV route, Automatic Trailer Loading, added to their materials handling system. 


Close up of the driverless AGV forklift with forks shifted left.

Just a short time ago getting robot industrial arms to palletize products as they come off the end of the assembly line was a difficult task.  Robot industrial arm builders still hold up palletizing as one of their crowning achievements and each one installed remains a custom job.  

Since manufacturers have no control over what trailer shows up at the dock for loading, loading every truck trailer becomes a custom job.  The trick is to automate the customizing process so the AGV forklift can look inside the trailer, size it up, plan the load arrangement and start packing the truck with product.  To be effective this all has to be done in real-time.  A combination of improved sensors and improved computers has made it possible for AGV's to use trailers that have not been adapted for AGV use, "as they are."

A good example is Egemin's TLVs - Trailer Loading Vehicles that are built using off-the-shelf components and are capable of speeds up to 100 m per minute carrying up to 5 tons.  They use flexible transfer elevations and load patterns that adapt to application requirements.  A graphical touch screen on the machine is for when humans want to interact with the machine. The choice of manual or automatic vehicle dispatch adds to the flexibility needed in loading dock situations. Some of the off-the-shelf components are: Sick® laser bumper safety system, Electric steer/drive assembly, Industrial lead-acid batteries, PC onboard running Windows XP®,  and RF Ethernet (802.11).   The software is divided into 20 function modules and each module contains about 10,000 lines of code.  The heavy-duty welded steel framework has a durable powder coat finish to keep this high tech machine looking cool for a long time. 

"Automation is going to make it possible for US manufacturers to compete in the world market. The more automation a manufacturing plant has the lower their operating costs are." -- Dave Noble - Director of Marketing and Communications - Egemin Automation.

Google Lunar X-Prize update
Richard Core - Vice President Network Operations - ISPhone is volunteering as a programmer for the FREDNET Team competing for the Google X-Prize.  While the rules only require landing and operating a lunar rover on the surface of the Moon by remote control, he believes that autonomous operation is going to be an important part of his team's rover operations.



GO ROBOTS !

Posted by Paul Grayson on November 9, 2007 | Comments (0)