The depth and diversity of applications show machine vision's strength beyond its dominant use for inspection. Also, overall purchases are expanding, according to research by Control Engineering/Reed Research Group. Survey results are based on responses from 182 subscribers, all of whom buy, specify or recommend machine vision products. About 35 percent of survey respondents expect machine-vision purchases to increase in the next year; with 54 percent expecting similar expenditures.
Machine vision use is in the double digits for more than 15 applications (see graphic).
The top applications are inspection, bar-code reading, motion control, gauging and robotics. The largest growth from 2004 to 2005 occurred in motion control; continuous processing; verification; diagnostics, testing and maintenance; System Control and Data Acquisition (SCADA); machine control; Computer Numerical Control (CNC) equipment; and discrete product manufacturing.
Among those using vision, 61 percent do so for in-plant requirements; 17 percent for OEM (original equipment manufacturer) resale requirements; and 22 percent for both OEM and in-plant requirements.
Regarding networks attached to machine vision, in 2004, the survey respondents predicted that their use of Ethernet would soon overtake RS-232 as the dominant network. Ethernet use did move from 65 percent in 2004 to 77 percent in 2005, and RS-232 moved from 73 percent down to 69 percent. Other notable increases in networking use with vision systems, from 2004 to 2005, were DeviceNet from 36 percent to 40 percent, Modbus from 22 percent to 28 percent, and Profibus-DP from 20 percent to 25 percent.
Other emerging network communication methods include EtherNet/IP, Modbus/IP, Profinet and OPC.
About 52 percent of those responding used smart vision sensors in 2005, compared to 46 percent in 2004. About 83 percent said those smart vision sensors met requirements, compared to 90 percent in 2004. Write-in comments on satisfaction mentioned the superiority of smart sensors compared to human inspection, the ease of programming and high success rates. Write-in reasons for dissatisfaction noted concerns about accuracy.
In the survey results, the leading three product-selection criteria when choosing machine vision are performance, technical support and ease of use (see graphic). Seven requirements ranked higher than price in importance.
Perceptions of cost did't change much from the prior survey in 2004: 57 percent of respondents say machine vision is't too complex or costly to implement; 43 percent say it is, about the same as last year. Not surprisingly, in 2005, capital budgets are less of an impediment to increasing machine vision investments. In 2004, capital was the key obstacle to investing in machine vision for 46 percent. Just 39 percent saw that as the key problem in 2005. Its priority compared to other automation was an impediment for 14 percent in 2004 and for 19 percent in 2005.
Other obstacles in the 2005 survey to more use of machine vision were: understanding of vision technology, 12 percent; acceptance by factory personnel, 10 percent; engineering resources, 10 percent; difficulty of use, 4 percent; and other, 7 percent.
System integrators are getting more machine-vision business, perhaps to help those with a lack of in-house resources. Integrators used for vision system projects jumped from 19 percent in 2004 to 25 percent in 2005; those planning to use increased slightly, 16 to 18 percent.