COBOT & ISO/TS 15066 SPECIFICATION
1.0 What is ISO/TS 15066?
? ISO/TS Technical Specification
– A normative document representing technical consensus within an ISO committee
– It is “more” than a technical report, expected to become a standard – but not quite ready to be a standard.
? Provides guidance currently not in ISO 10218-1 & -2
– Collaborative operation consist of approximately eight pages out of 152 total pages.
– ISO 10218-1 first introduced in 2006, revised in 2011.
– Collaborative was originally anticipated to be a unique operating condition for “typical” industrial robots.
1.1 Philosophical Background
“Why not have a human contact a robot system if the result is no harm to the human(s)?”
Contact similar to touching a stopped robot?
–When does repeated contact, that is initially without pain or injury, become painful and not acceptable?
?Human factors, ergonomics…
–Hence “collaborative operation”
?If the robot is wimpy (or called “safe”) and application is juggling explosives or knives, is this is an acceptable collaborative application? NO
1.2 ISO & R15.06 “Words”
Shall Normative or mandatory requirement
Should Recommendation or good practice
May Permissive or allowed
Can Possible or capable – statement of fact
Notes are informative: provides information or explain concepts.
1.3 Terminology
Robot – Robot arm & robot control (does NOT include end-effector or part)
Robot System – Robot, end-effector and workpiece +
Maximum space
–Space within which a robot system CAN move
Restricted space
–Portion of the maximum space restricted by limiting devices that establish limits which will not be exceeded
Operating space
–Portion of the restricted space that is actually used while performing all motions commanded by the task program
Safeguarded space
–space defined by the perimeter safeguarding
Operator(s) – All personnel, not simply production operators. Includes maintenance, troubleshooting, setup, cleaning, production…
1.4 Terminology from R15.06 and ISO 10218
? A collaborative robot is a robot that CAN (capable) for use in a collaborative operation
– Collaborative operation (Part 1, 3.4) – where purposely designed robots work in direct cooperation with a human within a defined workspace
? Uncovered come inconsistencies to correct: robot vs robot system, collaborative vs co-located.
2.0 Collaborative Risk Assessment
? Same process/methodology as “standard” (non-collaborative) application
? Plus need to assess added conditions (TS, 4.2)
– Intended and reasonably foreseeable contact(s) between portions of the robot system and an operator (human)
– Contact type to be determined (transient or quasi-static) for each body part(s) affected
– Frequency and duration of contact
2.1 Collaborative Operation
Four (4) techniques for collaborative operation (Part 1, 5.10; Part 2, 5.11) for collaborative applications (can be a mix of the following) while in AUTOMATIC mode:
?A collaborative application could use 1 or more of the following techniques.
2.2 Safety-Rated Monitored Stop
Allows for direct operator interaction with the robot system under specific circumstances
? Safety-rated stop condition before operator enters
? Drive power remains on
? Motion resumes after operator leaves workspace
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– Robot motion resumes without additional action
? Protective stop issued if stop condition is violated
Applications
? Direct part loading or unloading to end-effector
? Work-in-process inspections
? When 1 moves (not both) in collaborative workspace
? Used with other collaborative techniques
2.3 Hand-Guiding *automatic, not teaching
Operator uses a hand-operated device to transmit motion commands
? BEFORE the operator enters the collaborative workspace, the robot <system> achieves a safety-rated monitored stop.
– Drive power remains on
? Operator grasps hand-operated device (includes an enabling device), activing motion/ operation
? Non-collaborative operation resumes when the operator leaves the collaborative workspace
Applications
? Robotic lift assist
? Highly variable applications (acts like a manually “tool”)
? Limited or small-batch production
????(??0)= ???+ ????+ ????+??+ ????+ ????
????(??0) = Protective separation distance
??? = The operator’s change in location
???? = The robot’s change in location
???? = The robot’s stopping distance
?? = The intrusion distance that a part of the body can move toward the hazard zone prior to actuation of the safeguard
????+ ???? = Position uncertainty for both the robot and operator
2.4 Power and Force Limiting
Physical contact between the robot system (including the workpiece) and an operator can occur either intentionally or unintentionally.
? Robot systems required to be specifically designed for power and force limiting
? Forces that can be exerted are required to be limited robot, end-effector, workpiece
? Robot system reacts when contact occurs
– Contact could be quasi-static (pressure) or transient (dynamic)
Applications
? Small or highly variable applications
? Conditions requiring frequent operator presence
2.5 Power and Force Limiting Risk
Risk reduction for potential contact, where there will be no harm to the operator:
– Identify conditions for such contact to occur
– Evaluate risk potential for such contacts
– Design robot system & collaborative workspace so contact is infrequent and avoidable
– Consider operator body regions, origin of contact event, probability or frequency, type (quasi-static or transient), forces, speeds…
Contact to head, throat & neck to be prevented
Summary
Collaborative robotics is NEW!
– It is a paradigm shift where previously we separated the robot system from people.
– Allows more interaction & sometimes contact between the robot system and people.
? Some applications might not require “traditional safeguarding”.
How did this happen?
– Improvements in safety controls and added safety-related functions and features in robots
– Requires risk assessment and very careful consideration.
– Do NOT presume that a robot can be used for collaborative operation – the application determines whether the robot system can be collaborative.
Bachelor's Degree( Sunderland Uni UK),Masters Degree(Aston UniUK), MBA(Open Uni UK) ,Kallithea Secondary School,Athens
2 年Excellent George. When I wrote my book about Protection, Health and Safety -about 2 years ago ( in Greek ,now in process to translate and issued in English) -I did not include a chapter dealing with safety/protection issues pertinent to welding robots and cobots namely for two main reasons. 1. I do not have any practical experience and knowledge about this particular very specialised field so I thought that it was not wise to write about something that I was not familiar-knowledgeable with. 2. It is a new area ,especially the cobots and my understanding is that the safety aspect is not yet very developed or matured to say the least. Especially, Welding cobots -by the nature of this process- are even more dangerous and their risk assessment is much more complicated, at least according to my own understanding. However, articles like the one above serve very well to initiate a certain closure of the existing knowledge gap that currently prevails in the industry in general, my view again. Thanks and Regards GA