| The design and layout of a piece of equipment's | | | | Cognitive ergonomics takes special importance |
| knobs, handles and other manual controls is an | | | | when applied to industrial applications. A badly |
| important consideration both for ease of | | | | designed copy machine might be frustrating but |
| operation and worker safety. Manufacturers who | | | | badly designed factory equipment could lead to |
| pay careful attention to the ergonomics of the | | | | accidents such as hazardous spills. Industrial knobs |
| design will create equipment which is more | | | | and dials should be placed with both ease of use |
| pleasant to use and which creates less worker | | | | and worker safety in mind. |
| fatigue and injury. | | | | In a crisis, a worker needs to locate emergency |
| Repetitive Motion And Strain | | | | manual controls such as equipment cutoffs or |
| The most commonly emphasized type of | | | | flow control knobs instantly. There is no time to |
| ergonomics is physical ergonomics. This field | | | | search for them among other controls. Placing |
| focuses on the worker's body and how improper | | | | these controls in a separate area of the console |
| work positions can lead to a number of serious | | | | against a red background intuitively says |
| medical problems such as repetitive motion | | | | "Emergency" even to someone who's never seen |
| injuries. | | | | the equipment before. |
| Consider a machine that reserves the most | | | | Commonly used controls should be placed in |
| accessible parts of the equipment for displays, | | | | obvious locations and well labeled. Knobs can be |
| relegating levers and other controls to the sides | | | | differentiated not just by their labels but by color |
| and rear. Workers have to bend and twist to | | | | and shape, reducing the chance workers will |
| reach the manual controls. Doing this day after | | | | accidentally give the wrong commands to the |
| day forces them to put their bodies in unnatural | | | | machine. Controls used more rarely might be |
| positions and expose themselves to unusual | | | | placed out of immediate line of sight but still need |
| stresses. These stresses can cause tendonitis, | | | | to be clearly identified. |
| muscle strain or even fractures and more serious | | | | User-Designed Controls |
| problems. | | | | Often a design that looks good on a CAD drawing |
| The stress doesn't have to be severe to be | | | | doesn't work in actual use. The problem might be |
| dangerous. Hand wheels mounted too low could | | | | knobs placed in awkward positions, confusing |
| force a worker to bend over to control the | | | | labels on similar switches, or any one of a |
| equipment, eventually leading to low back | | | | thousand other things. Control design is as much |
| problems. Knobs placed high force workers to lift | | | | of an art as a science. The most successful |
| their arms out of comfortable positions, stressing | | | | control schemes involve user input. |
| the joints and muscles. | | | | When engineers work with end users for control |
| Stresses that seem trivial become magnified | | | | development, they create better-designed |
| when workers are exposed to them day after | | | | products. Operators face situations in day-to-day |
| day. Some repetitive motion injuries surface only | | | | use that engineers might not consider and are |
| after months or years of abuse, often from | | | | sources of valuable advice on placement and |
| seemingly benign activities. Consider one of the | | | | design of knobs and other controls. User input is |
| most common sources of repetitive motion | | | | most valuable during the prototyping stage, but |
| injuries, the computer keyboard. A slight change in | | | | worker criticism of an existing piece of equipment |
| wrist position can be the difference between | | | | is useful when planning the next model or even a |
| comfortable typing and carpal tunnel syndrome. | | | | seemingly unrelated device. |
| Intuitive Control Layouts | | | | Manufacturers should partner with a good supplier |
| While injuries are a common focus of ergonomics, | | | | of industrial controls. The supplier should have long |
| the science covers other aspects of control | | | | experience with many different control |
| design as well. Cognitive ergonomics focuses on | | | | components and offer a wide line of products. |
| how our mental processes interact with the | | | | Ergonomic design is about finding the ideal |
| equipment. The goal is to create intuitive controls | | | | controls, not something that is "close enough". |
| that are easier to learn and use. | | | | Suppliers should provide fast turnaround so design |
| Badly designed manual controls frustrate users. | | | | changes can be implemented quickly. |
| When a worker can't even find the power switch | | | | External controls deserve as much attention as |
| among a confusing array of knobs, dials and other | | | | the internal parts of a piece of equipment. A |
| hardware that doesn't bode well for how easy | | | | machine with a well-designed control scheme will |
| the machine is going to be to operate once it's | | | | be safer, do the work better and provide a |
| turned on. Using the equipment becomes stressful | | | | better experience for users. |
| and inefficient. | | | | |