Collaborative Robotics in Today’s Industries: Qualitative Risk Assessment and Case Studies
Mollie Anderson, MSSM
Principal Consultant BSI EHS Services and Solutions
2
Mollie A. Anderson, MSSM
• Principal Consultant, Manager
• BSI EHS Services and Solutions – Hillsboro, OR
• Experience with high technology industries and semiconductor
• Product safety engineering, hazard analysis, and risk-assessment methodologies; a solid foundation for robotics
• Global and local regulatory compliance, and EHS program management and oversight
Your Speaker
Image Placeholder
(conventional robot)
3
• Robotics
– Brief history
– Applicable regulations, industry consensus standards, and best practices
– Industry use of conventional robots vs. collaborative robots
• Understanding the Risk Assessment for Robotics
– Risk assessment
– Risk mitigation
– What is acceptable risk?
• Case Studies
– What do you need to know?
– Risk assessment examples
Agenda
Robotics Early History of Robots
1898 Nikola Tesla – debuts first ever radio controlled vessel
1920/1921 Karel Capek – the word “Robot” was introduced in the play “R.U.R”
4
Today’s Industries – Rapidly Expanding Use of Collaborative Robots
Photo credit: Precision Automation
Photo credit: Kuka
Photo credit: Epson Photo credit: Fanuc
Photo credit: Universal Arms Photo credit: Denso
5
6
• Regulatory and Accepted Industry Best Practices
– Robotics and Automated Systems Programs widely reference the industry consensus standards considered as best practice:
• ANSI/Robotics Industries Association R15.06-2012, Industrial Robots and Robot Systems – Safety Requirements
– Harmonized with robotic standard, International Standards Organization (ISO) 10218-1,-2
– Requires risk assessment for collaborative robotics – industrial robots used in collaborative modes
• Some additionally applicable Harmonized and Recognized Standards
• EN ISO 12100:2010 Safety of Machinery – General principles for design – Risk assessment and risk reduction
• EN ISO 13849-1:2015 Safety of Machinery – Safety related parts of control systems – Part 1 and Part 2
• EN ISO 13850: 2015: Safety of Machinery – Emergency stop function – Principles for Design
Robotics
7
Additional industry guidance:
• ISO/TS 15066: Robots and Robotic Devices – Collaborative Robots
• Specifies more specific requirements for collaborative robotics
• Defines speed and force consideration depending striking which part of the body
ISO-TS-15066 Biomechanical Limits
Understanding Risk Assessment – Collaborative Robotics
8
Industrial Robots: Programmable, multi-functional devices designed to move or interact with 3-axis or more, in pre-programmed motions to perform a variety of tasks
Robotics
Image Placeholder
(conventional robot)
Image Placeholder
(collaborative robot)
Conventional Robots Collaborative Robots
Photo credit: Baxter website
9
• Perform work in place of humans
• Automated interaction with materials using pre-programmed motions
• No regard for the people working around them
• Accidents are prevented using fences and cages
• Perform a variety of tasks
– Assembly
– Materials Handling
– Laser Etching, Welding, and Polishing
– Reliability Testing
Robotics
Image Placeholder
(conventional robot)
Conventional Robots
What is a Conventional Robot?
• Work in direct cooperation with a human within a defined workspace
• Easy to assemble, program, and operate
• Multiple, integrated, interactive safety features
- Can present special safety challenges
• Combine the human’s reasoning ability and adaptability with the endurance, strength, and precision of robots
Robotics
Image Placeholder
(conventional robot)
Photo credit: Kuka
10
Image Placeholder
(collaborative robot)
Photo credit: Universal Arms
What is a Collaborative Robot?
Conventional Robot Example Collaborative Robot Example
• Parts move into Robot’s restricted area via conveyor
• Robot picks up part, rotates into proper orientation, and places parts into a space on a pallet
• Pallet is moved out of restricted area via another conveyor
• Parts move into Robot’s restricted area via conveyor
• Robot picks up part, rotates into proper orientation, and places parts into a space on a tray
• Person takes parts from tray as needed
12
Understanding the Risk Assessment Process for Robots (Conventional and Collaborative)
Image Placeholder
(robot in use)
14
• Robotic Safety Programs
• Risk Assessment
• Training Program Development
• Safety Bulletins
Understanding Risk Assessment
Photo credit: Universal Arms
What is Needed?
15
Risk Assessment Basics
– Systems scope determination
• In what environment will the robot be used?
• Are there enclosures, vision systems, light curtains, etc.?
• Which end effectors will be used?
• What objects will be a part of the operation?
– Identification of risk sources
• Impact, pinch, crush, entrapment, entanglement, or other hazardous situations
– Use cases and tasks
• Installation and Set-Up
• Teaching
• Operations
• Maintenance
• Troubleshooting
Understanding Risk Assessment
16
Understanding Risk Assessment
Evaluating the potential for programming errors during robotic system set-up, teaching, and maintenance
Determining if there is sufficient speed and separation, power and force limiting, and guarding to prevent unauthorized access to the robotic system working area
Determining adequate control of mechanical hazards: crush, impact, pinch, entrapment, and entanglement
Determining adequate control of hazardous energy during maintenance activities (e.g., electric or pneumatic energy sources, oxygen-deficient environment)
Risk Assessment Examples
17
Estimation of risk
– Direct observations, document review, and interviews
– Risk ranking
Risk acceptability
– What is acceptable risk?
– What actions are required to reduce risk?
Additional risk-reduction process and considerations
– Avoid creation of additional hazards with the robotic safeguards
– Non-robotic and machine hazards once contained by safeguarding with traditional robot systems may be exposed during collaborative operation
Understanding Risk Assessment
Risk Assessment Basics
18
Understanding Risk Assessment – Collaborative Robotics
Preventing the possibility of inadvertent contact which may cause harm
Limiting the speed and position, power, and force of the collaborative robot
Minimizing the time and distance for the collaborative robot to come to a stop when required
Controlling the hazards caused by the work piece, end effector, peripherals, or application devices; consider ergonomic risks
Risk Assessment Examples
• Industrial robots in collaborative application
• Integrated safety features
– Safety-Rated Monitored Stop
– Speed and Separation Monitoring
– Hand Guiding
– Power and Force Limiting
Understanding Risk Assessment – Collaborative Robotics
Image Placeholder
(collaborative robot)
Collaborative Robots
Photo credit: Denso
19
• Robot and operator may move concurrently in the collaborative workspace
– Maximum permissible robot speed is determined by risk assessment
• Light curtains or pressure-sensitive mats are often used
Understanding Risk Assessment – Collaborative Robotics
20
Speed = Vmax
Speed = 0
Speed and Separation
21
Power and Force Limiting by Inherent Design/Control
• Robot sensors detect a contact between operator and the robot and stops to avoid personnel injury
– Passive compliance (mechanical) – avoids collision, or will move in the opposite direction avoiding injury
• Robot can only impart limited static and dynamic forces
– Integrated sensors – “feel” external forces
– Overcurrent detection – detect when a collision occurs: software generates a security “stop”
Understanding Risk Assessment – Collaborative Robotics
Force = Fmax
Force < Fmax
23
Understanding Risk Assessment – Risk Assessment Multipliers Degree of Possible Harm (DPH)
0.25 Scratch/Bruise
0.5 Laceration/cut/mild ill health effect/minor burns, minor muscle strain
3 Fracture minor bone – fingers, toes, severe muscle strain
5 Fracture major bone – hand, arm, leg
8 Loss of 1 or 2 fingers/toes or major burns
11 Leg/hand amputation, partial loss of hearing or eye
15 Amputation of 2 legs/hands, total loss of hearing/sight in both ears/eyes
25 Critical injuries or permanent illness/condition/injury
40 Single Fatality
65 Catastrophe
Possibility of Occurrence of Hazard Event (PO)
0.05 Almost impossible
1.25 Unlikely
2.5 Possible
4 Probable
6 Certain
Possibility of Avoidance (PA)
0.75 Possible
2.5 Possible under certain circumstances
5 Not possible
Frequency of Exposure (FE) 0.5 Annually
1 Monthly
2 Weekly
3 Daily
4 Hourly
5 Constantly
24
Risk Assessment – Acceptable to Unacceptable Risk
Understanding Risk Assessment – What is Acceptable Risk?
PHR Risk Comment
1-10 Negligible Risk Presents practically no risk to health and safety; no further risk reduction
measures are required.
11-20 Very Low Risk Presents very little risk to health and safety. No significant risk reduction
measures are required; may necessitate the use of personal protective
equipment and/or training.
21-45 Low Risk Risk to health and safety is present, but low. Risk reduction measures must be
considered.
46-160 Medium/Significant Risk The risk associated with the hazard is substantial enough to require risk
reduction measures. These measures should be implemented at the next
suitable opportunity.
161-500 High Risk Potentially dangerous hazard, which requires risk-reduction measures to be
implemented urgently.
501+ Very High Risk Risk-reduction measures should be implemented immediately; corporate
management should be notified.
25
Understanding Risk Assessment – What is Acceptable Risk?
Credit reference to Robotiq and Pilz Automation
26
Understanding Risk Assessment – What is Acceptable Risk?
Credit reference to Robotiq and Pilz Automation
Robotics – Case Studies
28
What can we ask ourselves, our management, and site staff?
• Do we currently use robotics?
- Are we having any issues or concerns voiced?
- Do we have a robotics safety program in place?
- Are we utilizing conventional or collaborative robots?
• Are we thinking of utilizing robots?
- Are we considering the use of collaborative robots for manufacturing, R&D testing, or labs?
- Do we need a robotic safety program which also addresses collaborative robots?
- Do we need a risk assessment for our specific integration and use of robotics?
- Have we considered safeguards, such as vision sensors, light curtains, or even fencing?
• Do we have any robotic training needs?
Robotics – What do You Need to Ask?
29
• Develop Robotic Safety Programs
• Risk Assessment
• Training Program Development
• Robot Safety Bulletins
Robotics – What Do You Need to Know?
What Can You Do? How Can You Help?
30
Recent Risk Assessments (Examples)
Hazards/Recommended Safeguards
• Personnel (hand, arm, body) within restricted work zone of robot (Impact, Entanglement, Crush)
– Utilize collaborative robot or collaborative operational mode
– Identify robot work zone and visual indication of pending operation
– Remote access to control robots; local control override
– Physical barriers around robot, light curtains, and pressure-sensitive mats
• Consider calibration vs. operations
– Ensure EMO for robot and associated robot systems together
– Identify confined space applicable rqmts
Small, Quick Robots
31
Recent Risk Assessments (Examples)
Hazards/Recommended Safeguards
• Personnel unable to know which robot is active (Impact, Entanglement, Crush)
– Visual indication of which robot is in operational mode
– User interface screen to identify robot modes
– Consider co-located robotic or other lab activities
– Remote access to control robots; local control override
• Label or placard to identify if robot is capable of remote start
– Personnel awareness training
Lab or Desk Top Robots
32
Recent Risk Assessments (Examples)
Hazards/Recommended Safeguards
• Object or person in path of mobile robot travel (Impact)
– Robot ‘along for the ride’ with an AGV
– Separate travel paths for personnel and mobile robots
– Vision sensing/cameras to identify obstacle and go around
– Limit speed of travel
– Light or sound indicators
• Mobile robot blocking emergency egress path during emergency
– Programming designates “safe zone” or a “stop in place” for emergency scenarios or failure of communications
Mobile Robots / AGVs
Summary
Moving Humans and Collaborative Robots Closer Together
Mollie Anderson, MSSM Principal Consultant, Manager
BSI EHS Services and Solutions [email protected] PH: 503-351-0725
Contact
Thank You!