February 2002
Automation vs. Mechanization By Mike Porter

Mechanization is normally defined as the replacement of a human task with a machine. Automatic transplanters are an example of mechanization. But, true automation encompasses more than mechanization. Automation involves the entire process, including bringing material to and from the mechanized equipment. It normally involves integrating several operations and ensuring that the different pieces of equipment talk to one another to ensure smooth operation. Many times, true automation requires reevaluating and changing current processes rather than simply mechanizing them.

One of the key concepts in automation is differentiating between mechanization and automation. At a recent trade show in Europe, I saw an interesting example of mechanization. On display was a piece of equipment that was trimming boxwood into a ball shape. It accomplished this by mechanical hedge clippers that replicated the motion of a human. While clever, this device is not automation.

A Complete Package

An automatic transplanting line can be used as an example of automation. A typical line would consist of automatic destackers for trays and automatic dispensers for pots. These two machines would be connected by means of a conveyor to a flat filling machine that fills the destination trays with soil and levels the soil. The flat filler would be connected by conveyor to an automatic transplanter. A second conveyor could be used to feed source trays into the transplanter. After transplanting, the destination trays would move onto another conveyor, which could feed an automatic tagging machine, and then go through a watering tunnel before being placed onto a final conveyor to be staged for delivery to the greenhouse, a process that can be automated as well. The transplanter itself will normally account for 50-60 percent of the total cost of the line.

Because every piece of equipment in such a line is linked to every other piece not only physically but electronically, the line is truly integrated and will allow for maximum efficiency. Such a line can be run by one or two people, replacing the nine or 10 people required for a manual line. Typically, the cost per flat can be reduced by 50 percent. A future column will deal with cost justifications and payback periods, but obviously, the savings are significant. Because such lines are typically modular, the line can be installed over the course of a few seasons to spread out the cost.

The Next Step

To fully realize the potential savings, simply installing the equipment is not enough. Considerable planning is necessary. Since each change of source or destination trays requires some changeover of the machine, even if only a simple program change, scheduling production to minimize such changeovers is critical. Since humans are less sensitive to changes in products or trays, changing to more rigorous scheduling may require a significant cultural shift in your operation.

Human transplanters are also able to adapt to variable moisture content in plugs. Automatic transplanters, like all automation equipment, require consistency in the product being handled to achieve maximum efficiency. A learning curve will be necessary to determine the proper moisture. Again, this may require a cultural shift in your organization. This change will be rewarded not only by cost savings, but also by a marked improvement in the consistency and quality of your finished product. To some growers, this improvement in quality and predictability may be even more important than the cost savings.

While fewer people will be needed to operate a line, these people will need a higher skill level than current employees. For example, it will be critical to have a maintenance person who understands the equipment and takes ownership of it. Most manufacturers will offer training for these maintenance people. Most manufacturers, of course, also offer service personnel, but downtime is very costly during the peak season. The manufacturer's in-house support people should be able to troubleshoot 75-80 percent of all problems over the telephone when dealing directly with a skilled-grower maintenance person.

But again, this requires a shift in thinking.True automation requires not only mechanization but also integration of multiple operations, rethinking your scheduling and production plan, ensuring consistency in product and evaluating the people skills necessary to achieve your goals. One of the most important considerations before automation is whether or not you want to truly automate your production; you might simply need to automate, or mechanize, certain parts of the process.