Moving products around is mechanical work. When the work is done by a control system and actuators its mechatronics. Mechanical work, whether by humans, by horses, by hydraulics, electrics or whatever, is still work. Figuring out what technology approach will be the most cost effective way to get the work done is the challenge.
Many of the constraints of the work are environmental. If work is being done outdoors, then temperature and humidity are a factor. Felling trees and in the forest requires extremely high forces due to the work needed to cut through a tree and drag it to a truck to be hauled off for processing. Processing trees, even in a plant environment, requires some serious hardware, 125 horsepower band saws are not unusual.
Doing work on a ship or oil rig has additional constraints because of the presence of explosive fumes and fuels. Often the need to avoid any possibility of igniting a combustible atmosphere causes engineers to apply pneumatic control systems. Yes, there is still a compressor somewhere to generate the compressed air supply, but that is usually remote or contained to avoid exposure to the volatile atmosphere.
Environmental constraints come in many forms. Extremely high temperatures push the limits of what is possible. Making glass, semiconductors, and primary metal processing are all high temperature environments where engineers have developed whole technologies in order to bring us the materials we use in everyday life.
The simplest action of rolling or sliding becomes a real challenge when environmental constraints are added to the work statement. Sawdust becomes a potential abrasive in woodworking environments that can introduce severe wear in moving parts. Corrosive and explosion proof atmospheres as well as food industry applications introduce all sorts of chemical compatibility problems that require special materials and processes in order to meet strict guidelines for safety.
As always, resourceful engineers have worked out solutions for all of these difficult applications. One family of solutions to rolling applications is the use of all ceramic bearings. No steel, no lubrication. None is needed because the ceramics are extremely high purity to start with and have extremely high precision surfaces eliminating the need for lubrication. No outgassing or contamination to worry about.
Other solutions take the form of air bearings and non-contact material handling devices. Air bearings have become more readily available for conventional applications, but are particularly compelling in large machinery applications where precision is required. Large flat screen display glass presents unique challenges that successfully addressed using a combination of air bearing regions and vacuum regions to move the glass without actual contact and with overall flatness measured in millionths of an inch.
A unique solution in pneumatic material handling takes compressed air driven into a funnel shaped recess and creates a vacuum in the center and an air cushion at the edges where the air is exiting. This creates a vacuum pickup that never quite comes in contact with the part, leaving no marks. Perfect for solar cell and some food and beverage applications.
Engineers continue to meet the unique challenges of industry and create commerce at the same time. And that’s what it should be about.