11-08-2012, 10:27 AM
Industrial Robotics Standards
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INTRODUCTION
A standard is defined in [1] as:
"A prescribed set of rules, conditions, or requirements concerning definition of terms;
classification of components; specification of materials, performance, or operations;
delineation of procedures; or measurement of quantity and quality in describing materials,
products, systems, services, or practices."
A good standard under the proper market conditions can help to increase competition,
reduce the cost of products and services, break trade barriers, and expand markets. The
phenomenal success of the Personal Computer (PC) market is the best example of good
architecture and interface standards. An additional benefit is the countless lives which have
been saved and accidents which have been prevented by health and safety standards.
Due to space limitation only a brief review of the subject of industrial robot standards can
be provided here. The objective is to cover the following three subjects. Provide a brief
general description of the U.S. standards setting process. Describe a few of the most
important standards. Provide as many relevant references known to the author as possible.
SIGNIFICANT STANDARDS ACTIVITIES
U.S. Robot Performance Standard
This standard consists of two volumes. R15.05-1 covers the point-to-point and static
performance characteristics [see Appendix, Section U.S.A. Standards: #4], and R15.05-2
covers the path related and dynamics performance characteristics [see Appendix, Section
U.S.A. Standards: #6].
The philosophy of the U.S. subcommittee on robot performance standards R15.05 is to
write standards which are useful to buyers to help them select the best robot for their
specific applications.
ISO Robot Performance Standard
As the scope section of this standard states, the specified tests are primarily intended to
develop and verify individual robot specifications, prototype testing, or acceptance testing.
The philosophy of the ISO sub-committee that developed this standard was not to use it to
compare the performance of similar capacity and size robots like that of the US R15.05-1
and R15.05-2. The first version of this standard, ISO 9283:1990, did not even specify
standard test paths and test loads. The lengths of the paths and size of the test loads were
specified as a percentage of the robot workspace and rated load. Since no two robots have
the same workspace and rated load, it was not possible for them to be tested under the same
conditions, thus making comparisons very difficult. The U.S. sub-committee complained
to ISO about this, and ISO corrected the second version of this standard, which now
contains an annex listing standard test path lengths, loads (same as R15.05-2) and
velocities. The use of these standards is optional though.
U.S. Robot Safety Standard
Because of safety concerns, this is probably the most popular industrial robots standard in
the US [see Appendix, Section U.S.A. Standards: #7]. There are also European Union
[6], Japanese and ISO standards [see Appendix, Section International Standards: #4]. The
U.S. standard is currently under review. The new version will become available in 1998.
The discussion here will concentrate on the new version of the standard.
One of the fastest growing markets of industrial robots is that of used robots. Large
industrial users are modernizing their fleet of robots and selling the old used ones. An
industry of robot re-manufacturers has developed to re-build and re-sell these robots. The
RIA subcommittee that is responsible for the safety standard (R15.06) decided to
strengthen the section on ". . . remanufacture and rebuild of robots," to address the safety
concerns of users who want to buy these robots. This section contains a detailed list of
requirements that must be met by any robot that changes ownership (this assures the
healthy growth of this market).
CONCLUSIONS
Most of the industrial applications of robots today do not require high accuracy and
repeatability. Furthermore, manual teach programming is used for most of these
applications, which eliminates the effect of the kinematic mechanism model errors. For that
reason, there has not been a great demand for standard performance tests results from the
robot manufacturers. The situation is changing though more and more people realize the
economic benefits of off-line programming and a hybrid manual-teach-off-line
programming technique is growing in popularity. New robotic applications in arc welding,
optoelectronic devices assembly, etc., have high performance requirements. These new
developments might revive the interest in performance testing. Most users would like to
have application specific performance test results. Right now this luxury is only available
for a few big buyers.