Institute of Occupational Health, Safety and Ergonomics (ASER e.V.)

Corneliusstraße 31, 42329 Wuppertal, Germany

Assessment of risks related to

employee-cobot interaction

June 13th 2019

Dipl.-Ing. Christoph Mühlemeyer, M.Sc.

Institut ASER e.V. & GEWITEB mbH, Wuppertal

Internet & Further Information / Tools: www.institut-aser.de

EUROSHNET Conference 2019 12-14 June 2019 Dresden, Germany

Be smart, stay safe together - innovative products and workplaces

Agenda

1. Introduction

2. Methods

3. Results

4. Discussion

2

Institute of Occupational Health, Safety and Ergonomics (ASER e.V.)

Our Location in Wuppertal (NRW), Germany

3

Institute of Occupational Health, Safety and Ergonomics (ASER e.V.)

Our ongoing topics

4

ASERASER

Arbeitswissenschaftliche Bewertung von

Belastungs- und Beanspruchungsgrößen

(nach ASER , 1981)*ABB_0035b.CDR

sehr wahrscheinlich

wahrscheinlich

möglich

Grenzbereich (DLG)

belastend bzw.beanspruchend

gering belastend bzw.gering beanspruchend

sehr gering belastend bzw.sehr gering beanspruchend

Über-belastung

bzw.

Überbe-

anspruchung

VII

VI

V

IV

III

II

I

[m] > 420

[w] > 280

> 380 420£

> 250 280£

> 330 380£

> 220 250£

> 270 330£

> 180 220£

> 200 270£

> 130 180£

> 130 200£

> 80 130£

[m] £ 130

[w] £ 80

Eeff > 300

260 < Eeff 300£

220 < Eeff 260£

160 < Eeff 220£

95 < Eeff 160£

35 < Eeff 95£

Eeff 35£

Lr > 95

90 < Lr 95£

85 < Lr 90£

80 < Lr 85£

75 < Lr 80£

65 < Lr 75£

Lr 65£

AP > 52

48 < AP 52£

42 < AP 48£

34 < AP 42£

26 < AP 34£

17 < AP 26£

AP 17£

I II III V VIIVI

Belastungsintensität bzw.

Beanspruchungsintensität

Lärm-Beurtei-

lungspegel

Arbeitspuls-

frequenz

Lr [dB (A)] AP [1/min]AU [W] NET [°C]

Arbeitsenergie-

umsatz

Normal-

Effektivtemperatur

Eeff [W/m²]

Effektive

Bestrahlungsstärke

Akzeptanzschwelle

Toleranzschwelle

Arbeitsenergieumsatz-

Bewertungstufe

IV

40

37

33

31

25

19

36

33

31

29

22

17

33

29

27

25

19

15

30

26

23

21

16

13

28

23

19

17

14

11

26

21

15

13

11

9

25

19

11

9

8

7

* Müller, B.H.; Th. Hettinger (1981):

Hettinger, Th.; B.H. Müller, H. Peters (1981):

Müller, B.H.(1982):

Interpretations- und Bewertungsverfahren arbeitswissenschaftlich-ergonomischer Felddaten. Zeitschrift für Arbeitswissenschaft, 35 (1981), Heft 1981/2, S. 82 ff.

Hitzearbeit – Untersuchung an ausgewählten Arbeitsplätzen der Eisen- und Stahlindustrie. Forschungsbericht, Teil 1, Wuppertal, 1981

Synthetische Arbeitsplätze – Verfahren zur Entwicklung von arbeitsplatz- typischen Belastungs-Beanspruchungs-Profilen. Diss., Wuppertal, 1982

Klima am Arbeitsplatz und in der Arbeitsumgebung; Beurteilung des Klimas im Erträglichkeitsbereich.

Ergonomie - Bestandteil der Sicherheitswissenschaft. REFA, Berlin, 1989

Übersichtstabellen zur Belastungssituation am Arbeitsplatz. Fa 23 Bd. I Grundlagen und Methoden. Bd. II Eisen- und Stahlindustrie. BAU, Dortmund, 1990

* s.a. DIN 33403-3 (1988-06):

Müller, B.H. (1989):

Müller, B.H.; H. Peters, Th. Hettinger (1990):

EF 5095

Be

we

rtu

ng

s-

stu

fe

Research Methods

Measuring Devices

Development

Worldwide Instrument Implementation

& Ergonomics Trainings

Core Question & Classification

5

Aspect Specification

workplace area shopfloor / logistics

workplace status existing / already implemented

industry 4.0 type inherently safe cobot

impact type

safe product safe use (accidents)

guarantees a healthy use (short, mid &

long-term health effects)?

Do safe innovations

lead to healthy workplaces?

What has been studied

for this purpose?

Sawyer Cobot

6

Source: rethinkrobotics

Cobot-Interaction in Logistics

7

Sawyer

Lightweight Robot

1 jointed-arm

Display with

stylized eyes

Implementation:

Industrial Hall (Logistics)

Re-packaging of tubes on the assembly line

Shift system: 3 x 8h

Source: www.humarobotics.com

Agenda

1. Introduction

2. Methods

3. Results

4. Discussion

8

BDS-Instrument – Holistic Approach

Results & Modular System

BDS = Multilingual Instrument for Production Ergonomics, Risk Assessment with Expert Functions

Thematic BDS-Modules for Holistic Approach

Environmental

Conditions

Mental

Exposures

Physical

Exposures

PPE

Risk

Assessment

Maternity

Protection

Occupational

Health Care

Collective Bargaining

Agreement

Results & Expert BDS-Functions for Industrial Engineering & Ergonomists

Assessment

Profiles

Ideas for Improvement &

Simulation

Statistics, KPIs, Reports,

Expert Analysis, cadasters

Measures incl.

effectiveness check

BDS-Instrument

Focus of use for current study

BDS-Instrument’s Production Ergonomic Module was used to

check, if the cobot guarantees a healthy use

Main focus were the Physical Exposures & Mental Exposures

BDS-Instrument’s Simulation Functions were used to compare

the initial situation (human only) with the employee-cobot

interaction

BDS-Instrument – Basic Methodical Background

11

more red bars

=

more fatigue, more recovery time,

more complaints, more discomfort,

more disorders

=

more urgent need for action!

Task 1

Task 2

Task nTask name

Task pic

Workplace

Workplace name

Agenda

1. Introduction

2. Methods

3. Results

4. Discussion

12

employee (backward simulation)

13

Permanent trunk torsion > 10° (left/right)

54.000 hand movements for both hands

in total / shift

7 hours continuous static standing

…

50,3

Physical exposures

BDS Assessment level 1 2 3 4 5 6 7

employee-cobot interaction

14

+

53,6

Physical exposures

BDS Assessment level 1 2 3 4 5 6 7

Changes:

+ 2.500 movements per hand

per shift

7% KIM MHO rating points

increase to 53,6 rating points

(KIM level 4)

employee (backward simulation)

15

7 sec cycle time

only displacing tasks, no rotation

cycle dependend w/o buffer

…

Mental exposures

BDS Assessment level 1 2 3 4 5 6 7

employee-cobot interaction

16

Changes:

Reduction to 5 secs cycle time

Higher connection to the technical

process & fewer degrees of freedom

Substitution only after consultation

and after large delay

Less contact possibilities to other

colleagues, …

+

Mental exposures

BDS Assessment level 1 2 3 4 5 6 7

BDS-Instrument – Production Ergonomics

Results, KPIs & Reports

17

Workplace

BDS Results, KPIs & Reports

w/o

cobot

cobot-

interaction

KIM-MHO result (risk score) 50,3 53,6

Physical Overload factor / employee (BDS report) 6 6

Cycle time (duration) 7s 5s

Repetition of work tasks (BAB level) 7 7

Connection to the technical process (BAB level) 4 (5) 6 (7)

Age stability (BDS KPI) no no

Mental Overload factor / employee (BDS report) 6 7

MSD risk (AMR 13.2 criteria) yes yes

Ordinance on Occupational Health Care – Sect. 5 optional optional

Irresponsible Risk (§9 MuSchG criteria) yes yes

Production Ergonomics Rank 1 of 2 2 of 2

Generally recommended for shopfloor no no

Agenda

1. Introduction

2. Methods

3. Results

4. Discussion

18

Discussion

19

Cobot-implementation increased upper extremity risk

(hand-/arm-injuries, CTS, ...) necessary surgeries increase!

New inherently safe technology can worsen exposures!

no cobot-manufactor problem, but an end-user problem

Cobots ≠ Manipulators (LHC success) in terms of ergonomics

method/process training for industrial engineering

Improvement Implementation gets more & more complicated

extended improvement management required Methods

Always the same: Worldwide approaches & limits, more

qualification in companies, more stringent control, higher

penalties

holistic research is needed, e.g. for providing borders for

Law & Standardization, development of innovative ergonomic

solutions, …

Discussion

20

Benefits

Cost savings

Financial benefits

…

Costs

Investment costs

Ongoing costs

sick leave

follow-up costs

Risks

Project realization risks

Financial risks

Business risk

Initiation risk

Safety and Health risks

Business Cases

Time

TIMWOODS

…

Institute of Occupational Health, Safety and Ergonomics (ASER e.V.)

Corneliusstraße 31, 42329 Wuppertal, Germany

Thank You for you Attention!

Do you have questions / ideas? (voxr!)

Dipl.-Ing. Christoph Mühlemeyer, M.Sc.

Institut ASER e.V. & GEWITEB mbH, Wuppertal

Internet & Further Information / Tools: www.institut-aser.de

Email: muehlemeyer@institut-aser.de