Design and Virtual Prototyping of Human-worn Manipulation Devices

1. GRASP Laboratory Design and Virtual Prototyping of Human-worn Manipulation Devices Venkat Krovi Mechanical Engineering Dept. McGill University Peng Song GRASP Laboratory University of Pennsylvania Vijay Kumar GRASP Laboratory University of Pennsylvania Richard Mahoney Rehabilitation Technologies Division Applied Resources Corporation ASME DETC99/CIE-9029

2. MOTIVATION • Mass production fixed automation flexible automation • Mass customization • Agile manufacturing • speeds up the process of going from concept to production • Customized design and manufacture • Human-worn products (helmets, hearing aids, eye-glasses, wearable computers, ...) • One-of-a-kind products: Product volume is 1 (3-day cars, assistive devices, ...) • Human-worn manipulation assistive devices

3. WHY ASSISTIVE DEVICES? • In 1992, the cost of caring for quadriplegics was 11 billion dollars. • 10,000 new spinal cord injuries every year (55% are quadriplegics, 58% between 16-30 years old) • Population aging is increasing the number of people requiring physical assistance (est. 60 billion dollars annually. • Annual cost to assist in Activities of Daily Living is around $80,000.

4. WHY CUSTOMIZATION? • Variability exists in user needs across the population. Products must be designed and customized to match these individual user needs. • The device-user customization ensures comfort of user and enhances performance of the device.

5. HUMAN-WORN MANIPULATION DEVICES

6. HUMAN-WORN MANIPULATION DEVICES

7. GOALS • Identify and investigate the component technologies required for designing, customizing, virtually prototyping and finally fabricating human-worn manipulation assistive devices for the motor disabled. • Present a unified design environment which integrates these component technologies and aids the designer in shortening the design cycle. • The design-customization-integration process can be extended to many classes of human worn products.

8. KEYS TO CUSTOMIZATION 1. DATA ACQUISITION Measurement of the human user, the task, and the environment. 2. DEVICE DESIGN AND OPTIMIZATION Mechanism synthesis (generating the desired “output” motion/force from the specified human “input” motion/force), CAD modeling. 3. VIRTUAL PROTOTYPING AND EVALUATION Geometric and dynamic modeling of the human user, the designed product, and simulation of the human using the product prior to rapid fabrication.

9. 1. DATA ACQUISITION MOTION CAPTURE in 3-D Studio GEOMETRY CAPTURE in 3-D studio CUSTOMIZED MODEL

10. 1. DATA ACQUISITION:Measurement to models • Solid models generated from image data using • Multi-camera, multi-pose measurements • Cyberware 3D scanner • Meshed Solid models for • CAD (Pro/Engineer) • CAM (CNC machining) • FEM/FEA • Kinematic and dynamic models for • Virtual prototyping • Analysis and simulation • Provides important tools for • Re-design • Customization • One-of-a-kind prototyping • Reverse engineering

11. Geometric Mechanism Mechanism Geometric Degrees of Freedom Degrees of Freedom 2. DEVICE DESIGN AND OPTIMIZATION OUTPUT DEVICE INPUT DEVICE DESIGNER COUPLING Choices Choices AUTOMATION

12. Software: Pro/Engineer. • Parametric definition of parts. • Detailed geometric design capability. • Part vs assembly modeling. • Interfaces to analysis, FEM and CAMpackages. 2. DEVICE DESIGN AND OPTIMIZATION: Module DESIGN MODULE • Synthesis of feasible candidate designs to assist the designer in selecting suitable design. • Optimization and customization of the mechanism occurs here and then propogated on to the visual interface. CAD MODULE

13. 2. DEVICE DESIGN AND OPTIMIZATION: Process • Obtain kinematic model of movement and determine appropriate input motion. • Choose appropriate output motions. • Preliminary design: select candidate mechanism. • Use virtual models to investigate the mechanism. • Customize the mechanism to the individual user and build a virtual prototype. • After testing and evaluation, build the physical prototype.

14. 3. VIRTUAL PROTOTYPING AND EVALUATION • Parametric mapping • Kinematic and dynamic evaluation with a model of the user • Design optimization and customization • Virtual and physical prototypes of the input subsystem and effector subsystem

15. KINEMATIC GEOMETRIC MODELING MODELING DESIGN OPTIMIZATION DESIGN ENVIRONMENT Cyberware Video cameras range Manipulandum scanner 3-D model CENTRAL Motion Surface INTERFACE mesh VISUALIZATION DYNAMIC simulation (JACK, GeomView, ANALYSIS ProEnginer) CAD/CAM ProEngineer Off-the-shelf Customized components components MANUFACTURING

16. DESIGN ENVIRONMENT: Central Interface • Unified framework for analyzing data (geometry, kinematics, dynamics), testing (simulating) and evaluating products. • Graphical, user-friendly interface. • Heterogeneous data. • Modular. • Uses standard packages/formats.

17. DESIGN ENVIRONMENT: Central Interface

18. DESIGN SELECTION CASE 1: Head-controlled Feeding Device

19. VIRTUAL PROTOTYPING

20. VIRTUAL PROTOTYPING

21. FABRICATED PROTOTYPE

22. CASE 2: Head-controlled Painting Tool • DESIGN SELECTION

23. VIRTUAL PROTOTYPING

24. VIRTUAL PROTOTYPING

25. FABRICATED PROTOTYPE

26. FABRICATED PROTOTYPE

27. SUMMARY • Key Ideas • Integrated design environment aids the designer in the rapid realization of “one-of-a-kind” products customized to individual users • Only feasible designs are created by design module effectively reducing the optimization search space. • Virtual prototyping enables rapid evaluation within these feasible design choices. • Customized design methodology applicable to many classes of human-worn devices which need to be customized to individuals. • Limitation • The component technologies are often specific to the product