Ergonomics in the 21st Century: New Solutions for Old Problems Carisa Harris Adamson, PhD, CPE, PT

Transcription

1 Ergonomics in the 21st Century: New Solutions for Old Problems Carisa Harris Adamson, PhD, CPE, PT Asst. Professor, UCSF Department of Medicine Director, UC Ergonomics Research & Graduate Training Program I have no personal conflicts of interest to disclose. The UC Ergonomics Research & Graduate Training Program is supported by: Google Pentax Logitech Facebook/Occulus Learning Objectives Identify age old ergonomic issues that may be improved using new wearable technology. Identify 3 types of wearable technology being applied to ergonomics. Discuss applications of existing & evolving technology in ergonomics Identify how health/medical practitioners may use wearable technology to prevent and treat musculoskeletal disorders. 1

2 ERGONOMIC ISSUES THROUGH THE AGES ERGONOMIC ISSUES THROUGH THE AGES ERGONOMIC ISSUES THROUGH THE AGES 2

3 MSDs by Body Region Work Related Musculoskeletal Disorders (WMSDs) of the Neck, Back, and Upper Extremity, Washington State Workers Compensation Compensable (a) Claims, State Fund and self insured, Incidence per Median Type 10,000 FTEs (b) Lost Workdays (c) Median Cost (d) All $11,183 Back $6,032 Shoulder $28,228 Elbow/forearm $18,083 Hand/wrist $14,166 Knee $14,245 MSDs By Occupation Occupation Laborers and freight handlers Nursing aides and orderlies Incidence of Work Related Musculoskeletal Disorders in Private Industry, United, States, 2015 Number of Incident Cases Incidence Rate per 10,000 Workers 21, , Janitors and cleaners 15, Heavy and tractor trailer truck drivers 15, Emergency medical technicians/paramedics 3, Firefighters 5, Telecommunication line installers/repairers 2, /pdfs/ pdf Quantifying Physical Exposures. 3

4 Laboratory Approach Ergonomic Evaluation of Bed Making Among Hotel Room Cleaners Missing Markers. What about the other tasks? Pushing Supply Cart Cleaning Bathroom 12 to 20 Rooms/Day Making Bed Vacuuming Dusting Drawings taken from: resources housekeeping 4

5 e=brl Wearable Technology Applications Chart 2014%2Ejpg&title=Wearable%20tech%20application%20chart The BIONIC (WO)MAN Emerging Wearable Technologies in Ergonomics Inertial Measuring Units Electromyography Exoskeletons 5

6 Inertial Measuring Units (IMUs) gyro accel mag baro Sensor Fusion 3D angular velocity (rad/s) 3D acceleration (m/s 2 ) 3D earth magnetic field (mgauss) Drift free 3D absolute orientation (calculated) UWB RF GNSS 16 Activity Classification Algorithm Stand Accelerometer Data Walk Accelerometer Data Sit Accelerometer Data Activity Classification Algorithm 6

7 Behavior Cueing Framework Data Based Push Notifications SpineTrack 7

8 Physical Demands Assessment Summary Dashboard Probability of Lumbar Spine Disorder (RISK MODEL) LIFTRATE (LIFTS/HR) MOMENT (Nm) SAG POS (DEG) TWIST VEL (DEG/s) LATERAL VEL (DEG/s) 41 PROBABILITY OF HIGH RISK GROUP MEMBERSHIP (%) Probability of Lumbar Spine Disorder (RISK MODEL) 8

9 SpineTrack Performance Worker 1 Worker 2 Worker 3 Worker 4 Percent Probability of Belonging to High Risk Group 24% 21% 32% 40% Inertial Motion Capture 17 Synchronized Inertial Measuring Units (IMUs) report position, acceleration, velocity of segments and joints February 28,

10 Job Analysis Vivetech ViVeHuman February 28, Job (Re)Design through Simulation February 28, Wearable EMG q3 canadian vc deals/ 10

11 Wearable EMG labs 120 million series b wristband gesture tracking virtual reality/ Wearable EMG Purpose Develop a model to predict grip/pinch hand posture & force magnitude using IMU & wemg Quantify individual UE exposure to compare to thresholds (1kg Pinch Grip;4kg Power Grip) o Percent time in heavy hand exertion o Forceful repetition rate o % time spent in wrist deviation while in forceful exertion Use gold standard technique to compare with predictive model Harris-Adamson C, et al., Biomechanical risk factors for carpal tunnel syndrome: a pooled study of 2474 workers. Occup Environ Med 2014;0:1 9 11

12 Average R squared values for grip force prediction across 11 subjects. Average R squared values for pinch force prediction across 11 subjects. 12

13 14 Multimedia Video Task Analysis Hand Posture Prediction Hand Posture & Force Estimation 13

14 Disability Prevention Exposure N=340 (n=178) HR* Pace Change Hal Scale >4 & [ ] Hal Scale > [ ] % time in All Exertions >58% & 76% 0.81 [ ] % time in All Exertions >76% 1.96 [ ] Lost Time Total Repetition Rate >14 & [ ] Total Repetition Rate > [ ] Forceful Repetition Rate >3 & [ ] Forceful Repetition Rate > [ ] *All models adjusted for gender, age, BMI, study site & non overlapping exposures Passive Exoskeletons Passive Exoskeletons Arm Support Exoskeleton Weighs 12.4 lbs Provides 5 15lbs (70 200lb in) of support Allows for most of shoulder ROM Adjustable to fit 5% 95% population Trunk Support Exoskeleton Weighs 5 8 lbs Provides up to 30 lbs (min. of 120 lbin)of support No gait impedance Adjustable to fit 5% 95% population 14

15 Study Tasks Prolonged static posture Dynamic overhead drilling Welding, Mechanical work, Electrical work, Grinding, Inspection Automotive under body, Construction, Aviation Assembly Arm Exo Study Design Static posture Dynamic posture R1: Task 2lb tool 10 lb tool 2lb tool 10 lb tool No device Support = load* Self selected support No device Support = load* Self selected support No device Support = load* Self selected support No device Support = load* Self selected support R2: Support Within subjects 2x2x3 design: participants from local construction industry * Support = load determined by measured arm weight + tool weight Assessment Muscle Fatigue EMG (agonist & antagonist) Rate of Perceived Exertion Performance Productivity Usability Worker perception MSD Discomfort Overheating Device Comfort 15

16 Outcome Measures Muscle Activity Shoulder Flexors (anterior deltoid, pectoralis major, biceps long head) Shoulder Extensors (lattisimus dorsi, posterior deltoid) Spinal Extensors (erector spinae) Grip (FDS, ED) Rate of Perceived Exertion Outcome Measures Performance Static: accuracy & amount of line traced Dynamic: number of screws inserted Outcome Measures Discomfort (NPS 0 10) 2. On a scale of 1 5 please identify comfort of primary device contact points 3. Please identify any locations of discomfort from the device and if possible indicate its cause abrasion, pinching, pressure, heat * Questions repeated for R&L 16

17 Do No Harm Evaluation Assess Benefits & Challenges Extra weight Increased temperature Contact pressure points Implication on antagonist muscle groups Usability donning/doffing wearing over time Task based preferences Muscle activity during static work and use of heavy tool. Muscle activity during dynamic work and use of heavy tool. 17

18 Passive Exoskeletons Job Requirements Work Demand Worker Capacity Environmental Limitations Individual Needs Goals & Priorities Assist high risk workers (based on cumulative/ typical/peak exposure) Supplement aging/female workers Accommodate injured workers during RTW Wearable Technology Inertial Measuring Units Magnitude, velocity & acceleration of movement Static postures % time spent in different postures/ above thresholds Repetitive exertions Physical demands summary Posture/ Activity Detection Wearable EMG Muscle activity & activation patterns % time spent in different exertions Force prediction Hand posture prediction Passive Exoskeletons Increase Worker Capacity Supplement aging/ female workers Accommodate injured workers PROGRAM MANAGEMENT SURVEILLANCE JOB ANALYSIS MSD MANAGEMENT JOB DESIGN 18

19 A different approach to MSD prevention Emerging Solutions Question #1 The following is NOT a wearable technology that is being applied to solving ergonomic challenges: a) Inertial measuring units (IMUs) b) Electromyography c) Exoskeletons d) Video Monitoring 19

20 Question #2 Wearable technology in ergonomics can be used for: a) Surveillance b) Job analysis c) Job (re)design d) Musculoskeletal disorder management e) All of the above Question #3 Wearable technology may soon be used by medical/ health care practitioners to: a) Understand the physical demands of a job b) Support a quantitative approach to return to work c) Allow for accommodation by increasing worker capacity for earlier return to work or stay at work purposes d) Assist in directing injury prevention programs e) All of the above Questions & Comments Carisa.Harris-Adamson@ucsf.edu 20