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Human Robot Collaboration (HRC): Biomechanical Limits, Modeling and Testing to Support Safe Robot Contacts with Humans

IROS 2019 in Macau, China

This workshop will be held at  the 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2019) in Macau, China.


Joe Falco
National Institute of Standards and Technology (NIST)– United States 
E-mail:  falco [at] (falco[at]nist[dot]gov)  (Phone: +1 301-975-3455)

Dr.-Ing. Matthias Umbreit
Trade Association Wood and Metal – Germany 
Email: M.Umbreit [at] (M[dot]Umbreit[at]bghm[dot]de) 

Dr. Sungsoo Rhim
Kyung Hee University – Korea 
Email: ssrhim [at] (ssrhim[at]khu[dot]ac[dot]kr) 

Objectives (max. 600 words) 

A new class of robots  supporting human robot collaborative applications are designed to safely work alongside human. These robots are equipped with force sensing and active force control strategies or compliance through mechanical actuator technologies in order to limit forces and prevent injury upon contacts with humans.   To ensure that humans are tolerable to contacts by the robot, biomechanical pressure and force limits are being developed that are based on both injury and pain tolerance.  In addition to establishing these limits, other research areas include the development of models to predict robot parameters for safe human contacts and test methods to verify robot operation These tools are needed by the robot manufacturers as well as the application end-user before any system is commissioned for collaborative operation with humans.

This workshop, organized by individuals involved in the development of ISO 299 Robot Safety Standards to support human robot collaboration (HRC), will for the first time bring together researchers involved in the development of biomechanical limits, modeling, and test methods to support safe contacts with humans by collaborative robot systems with the goal of developing unified approaches to solving these difficult problems.  In addition, the workshop will help to inform the robotics community of this ongoing research that is crucial to successful implementation of safe collaborative robot applications.  The workshop will provide talks by leading researchers from both the biomechanics and robotics fields involved the development of pain and pressure based biomechanical limits as well as the associated modeling methods supporting low velocity robot contacts with humans and test methods to support the development of safe power and force limited robotic applications.  It will also include a poster session to showcase some of the most recent research within the academic community that supports safe collaborative operation, including robotic control, mechanics and sensing, to raise awareness and spur discussions amongst the robotics and biomechanics community.  The workshop will conclude with a one-hour discussion period and road mapping session to help unify the direction of this research community and promote collaboration amongst researchers.

Topics of interest

Provide a list of topics (keywords) addressed in the workshop/tutorial.

  • Human Robot Collaboration
  • Force Control
  • Compliance and Impedance Control
  • Compliant Joint/Mechanism
  • Biomechanical Limits
  • Impact Modeling
  • Safety Testing Devices and Methods

Speaker Information

Roland Behrens (Fraunhofer IFF, Germany)
Title:  From Head to Toe - Biomechanical Thresholds to Protect Robot Operators Against Injuries
Abstract:  In scenarios with close physical human-robot interaction, it is necessary to ensure that the robot cannot harm the human. This requires knowledge of the human’s tolerance threshold with respect to robot collisions, in particular for mechanical hazards like clamping (quasi-static contact) or non-constrained impacts (transient contact). According to the ISO/TS 15066, the threshold for collaborative robots used in the manufacturing is the onset of pain. It describes the transition from pressure stimuli to pain. One way to express the onset of pain are limit values based on physical quantities like force or normal stress. 

In our presentation, we introduce a volunteer study we recently finished. The goal of the study was to determine limit values for the pain threshold during quasi-static and transient contacts. Our methodology uses two different test rigs and a gradual increase of the stress intensity until the volunteer classified the contact as painful. We determined limit values for 28 different body locations for both forms of contact, which we will show and discuss in the presentation. 

The results from our study confirm that most limit values are only valid for a particularly shaped impact body. At the end of our presentation, we will introduce a methodology to create FE models which can be used to determine synthetic limit values for differently shaped impactors.


Nick Dagalakis (NIST)
Title: Engineering Biomechanics of Human Impact Injury with the Use of Human Tissue Biosimulant Artifacts
Abstract: The development of a new generation of industrial robots that can have multiple arms, are smarter, easier to program, and can work side-by-side with human workers and other robots, promises to revolutionize the manufacturing industry. The probability of this type of robots injuring humans, because of an impact or trapping has increased though. Impact biomechanics researchers have worked very hard to provide us with human body injury information, and body parts properties relevant to injuries resulting from an impact or trapping accident. Human impact injury biomechanics studies and testing, with the use of cadavers, or porcine tissues, are expensive and messy, which require special facilities, permits and specialized user training, which limit the number of studies and tests, that can be performed. For a thorough engineering study of impact biomechanics events, a researcher needs inexpensive, light weight, transportable to the work site, and easy to use test samples. For that reason, we have developed bio-simulant artifacts of different parts of the human body, for a variety of impact applications, that have made possible a better understanding of tissue impact or trapping damage, without the use of cadavers or porcine tests. These artifacts could be made from materials with mechanical properties like those of human soft or hard tissue of interest, for the type of impact being studied. The presentation will include description of specialized instruments for experimental mechanics testing of human biosimulant artifacts, ways to measure the severity and extend of human-robot impact injury and computer simulations of human-robot impact events with the use of human biosimulant artifacts.


Norbert Elkmann (Fraunhofer IFF, Germany)
Title:   New approaches to improve the design of HRC robot applications (Computer Aided Safety)
Abstract: Assistance robots sharing workspace with humans are an indispensable technology for the future. However, it must be ensured that people are not harmed. To realize an HRC application e.g. in the industrial domain, it must fulfill all the necessary health and safety requirements and be economically feasible. Currently, the engineering effort for the planning, implementation and safety certification of HRC applications is complex, costly and therefore often not economical.  In the presentation, novel tools for the effective planning and implementation of safe human-robot-collaboration (Computer Aided Safety, CAS) will be introduced. They consider the robot simulation, the layout of the application, the features of the safety sensors and the matching to the normative safety standards. Thus, it is possible to effectively plan an HRC application without prototypical setups, to check the safety certifiability, the necessary investments and the workspace requirements. In alignment with ISO/TS 15066, CAS modules are available for cases featuring collision management (Power and Force Limiting, PFL) and collision avoidance (Speed and Separation Monitoring, SSM).  The presentation concludes with an outlook on autonomous assistance robots and the safety and certification challenges.


Daniel Meixner (GTE)
Title:  HRC proven safety – measurment technology and methods for the validation of a HRC application
Abstract:  The evaluation of an HRC application with a force-power limitation requires resilient measurements of the contact situations. Impact and clamping measurements must be carried out with a  biofidel measuring system. In addition to the theoretical basics, simplified measurements for the free contact as well as considerations of the dynamic pressure are presented.


Tanyaporn Pungrasmi (Panasonic)
Title:  An Evaluation Technology of Safe Contact with Humans for Collaborative Robot by Pain Sensing System
Abstract:  Robots are now increasingly collaborating with humans in a public environment. In order to minimize the risk of human injury, there is a necessity for a safety evaluation. In this respect, an evaluation technology for safe contact using pain-sensing system which imitate the sensing location of pain receptors in human was developed. By using this system, two types of typical human pain (superficial and deep pain) are expected to be able to evaluate separately when contact is made. This system can be used to support the development of safe contact in robotic application and expand the robot market’s growth in the near future.


Nagarajan Rangarajan (NIH)
Title:  Modeling Human – Collaborative Robot Impacts
Abstract:  Coming soon


Sungsoo Rhim (Kyung Hee University, Korea)
Title: Collaborative robot who aware of its own collision risk and finds safe motion
Abstract: As the use of collaborative robots that share workspace with humans increases in the industrial environment as well as in non-industrial environment the collision safety issue of the human draws more attentions. There are many parameters affecting the collision safety of the robot and they vary along with various factors including the configuration of the robot and the tools used just to name a few.  Setting the credibility issue of the biomechanical thresholds available in many domains (including ISO/TS 15066) we already know that it is still very challenging task to estimate (and/or measure) the contact force and contact pressure that would be resulted in by the collision between the robot and the human. For the contact force and the pressure would depend on the complex non-linear function of the varying effective inertia of the robot, the contact speed between the robot and human and the shape and the mechanical properties of the contact surfaces at the given time of the collision.   Measuring the variation of the contact responses for the given robot per various operation conditions and environments would be a very much time-consuming and practically impossible task to cover all the potential use cases of the given robot.  This presentation introduces an initial attempt to estimate the collision risk of the robot in real-time while it is in motion using a mathematical collision model developed on the basis of the results from various bio-mechanical experimental performed in Kyung Hee University. The effectiveness of the approach has been experimentally verified. It also explains the use of the proposed approach for the robot to find safe motion in the face of unavoidable collision. 

Yoji Yamada (Nagoya University, Japan)
Title:  A Practical Study in Collaborative Robotics
Abstract:  In the first half of the talk, the presenter describes a potential runaway motion in the task space (PRAM-t) which covers not only the space which is defined by the currently regulated protective separation distance in normal operation but also the space which is estimated when the robot runaway motion is taken into account. The PRAM-t can be computed based upon the concept of dynamic manipulability ellipsoid. He stresses that it is indispensable to take the robot runaway motion into consideration to ensure a safe volume typically around the end effector in the framework of not only Input-Logic reliability block but Input-Logic-Output one. In the second half, he talks about implementation of a radar-type 3D safety-related sensor with the FM-CW (Frequency Modulated Continuous Wave) detection principle on a human-robot collaborative operation. The operation concerns battery assembly where the PRAM-t is introduced to determine the relative placement of a human operator and the robot. He demonstrates that the efficiency of the collaborative operation is improved by the use of the 3D sensor with respect to the cycle time and shop floor space compared with that in the case of applying a 2D laser scanner. 

Poster Session

  1. Entropic Risk Measure in Policy Search, David Nass, Boris Belousov, and Jan Peters
  2. Study on Verifying Thresholds for Mechanical Pain Caused by Human-Robot Transient Collision, Doyeon Han, Moon Young Park, Jiwong Lim, Chang Joo Lee, and Sungsoo Rhim
  3. A Real-time Collision Risk Evaluation and Safe Control Method Using Pre-trained Deep Learning Model, Heonseop Shin, Junsuk Choi, and Sungsoo Rhim
  4. Cooperative Handheld Robots: Anticipating Users and Assisted Remote Collaboration, Janis Stolzenwald and Walterio W. Mayol-Cuevas

Workshop Agenda




9:00am – 9:20am

Joe Falco

National Institute of Standards and Technology – United States


9:20am – 10:00am

Roland Behrens

Fraunhofer IFF, Germany

From Head to Toe - Biomechanical Thresholds to Protect Robot Operators Against Injuries

10:00am – 10:40am

Daniel Meixner,

GTE Industrial Electronics GmbH,


HRC Proven Safety – Measurement Technology and Methods for the Validation of a HRC Application


10:45am – 11:15am

Coffee Break


11:20am – 12:00pm

Sungsoo Rhim

Kyung Hee University, Korea

Collaborative robots who are aware of its own collision risk and finds safe motion

12:00am – 12:40pm

Norbert Elkmann

Fraunhofer IFF, Germany

New approaches to improve the design of HRC robot applications (Computer Aided Safety)

12:40pm – 1:00pm

Flash Poster Presentations


1:00pm – 2:00pm

Lunch/Poster Session


2:00pm – 2:40pm

Tanyaporn Pungrasmi

Panasonic, Japan

An Evaluation Technology of Safe Contact with Humans for Collaborative Robot by Pain Sensing System

2:40pm– 3:20pm

Nick Dagalakis

National Institute of Standards and Technology – United States

Engineering Biomechanics of Human Impact Injury with the Use of Human Tissue Biosimulant Artifacts

3:20pm – 4:15pm

Posters/Coffee Break


4:20pm – 5:00pm

Nagarajan Rangarajan

National Institute of Health,

United States

Modeling Human – Collaborative Robot Impacts

5:00pm – 5:40pm

Yoji Yamada

Nagoya University, Japan

A Practical Study in Collaborative Robotics

5:40pm – 6:00pm

Final Discussions


Created May 29, 2019, Updated January 14, 2020