University of Genoa PMAR – Department of Mechanics and Machines design Development of micro-tools...

University of Genoa

PMAR – Department of Mechanics and Machines design

www.dimec.unige.it/PMAR

Development of micro-tools for surgical applications

UNIVERSITA' DEGLI STUDI DI GENOVA

FACOLTA' DI INGEGNERIA

UNIVERSITE' PIERRE ET MARIE CURIE

LABORATOIRE DE ROBOTIQUE DE PARIS

PHD THESIS EN COTUTELLEXVII CICLE

SUPERVISORS: PROF. ING. Rinaldo MICHELINIPROF. ING. Philippe BIDAUD

STUDENT: Francesco CEPOLINA

18 November 2005

University of Genoa



Index

robotic surgery

MEMS technologies

modules design

system integration

University of Genoa



Robotic surgery

Robotic in-body equipment Active catheters EndoscopesAutonomous wormsNavigating pills

Remote-surgery environmentsOrthopaedic surgeryEye surgeryLaparo/thorax-tomic surgerySurgical end-effectors

University of Genoa



Active catheters

Esashi catheter

Olympus catheters

Tohoku University

www.olympus.com

University of Genoa


www.dimec.unige.it/PMAR Endoscope tip

Hirose and Ikuta endoscopes

State of art

Ikuta laboratory

Endoscopes 1 of 4

Hirose + Yoneda

Robotics lab

University of Genoa



LRP intestinal endoscope

Paris 6

Endoscopes 2 of 4

ARTS labPisa arthroscope

University of Genoa



Swiss endoscope

EPAM endoscopes

Dr. Gründler

Stanford Research Institute

Pennsylvania State University

Endoscopes 3 of 4

University of Genoa



Neuro-endoscopic operating instruments

Imperial College of London

Endoscopes 4 of 4

Grenoble University

Laparotomic endoscope

University of Genoa



Autonomous worms 1 of 3

Leuven intestinal worm Pisa intestinal worm

ARTS labKatholieke Uneversiteit

Leuven

University of Genoa



Leuven intestinal worm arms

Korea worm

Katholieke Uneversiteit

Leuven

Korea Institute of Science and Technology


University of Genoa



Korea impulsive wormKorea

Institute of Science and Technology Korea centipede worm


University of Genoa



Navigating pills

The Norika 3 pill

www.rfnorika.com

University of Genoa



Robotic surgery

Robotic in-body equipment Active catheters EndoscopesAutonomous wormsNavigating pills

Remote-surgery environmentsOrthopaedic surgeryEye surgeryLaparo/thorax-tomic surgerySurgical end-effectors

University of Genoa



Robotic surgical systems

University of Genoa



Eye surgery

Israel Institute of Technology

NASA Jet Propulsion Lab

Orthopaedic surgery

University of Genoa



Laparo/thorax-tomic surgery

The da Vinci® surgery system

http://www.intuitivesurgical.com/

University of Genoa



The ZEUS® surgery tools

da Vinci® surgery tools

http://www.intuitivesurgical.com/

Surgical end-effectors 1 of 4

University of Genoa




da Vinci® snake wrist

http://www.intuitivesurgical.com

Poland surgery gripper

Technical University of Lódz

University of Genoa



Michigan surgery gripper

Michigan State University College of Engineering


German Aerospace Center, DLR

German surgery gripper

University of Genoa



German forceps

Poland sewing effector

Warsaw University of Technology


Daimler Benz

University of Genoa



Minimally invasive surgery: clamps

F. Cepolina, R.C. Michelini, “"Robots in medicine: A survey of in-body nursing aids. Introductory overview and concept design hints."

2DoF 4DoF 4DoF

5DoF

5DoF5DoF

University of Genoa



Index

robotic surgery

MEMS technologies

modules design

system integration

University of Genoa



ELECTROSTATIC FORCE

Comb drive

Rotating comb drive

Wooble motor

MEMS technologies 1/4

PIEZOELECTRIC EFFECT

Multilayer piezoelectric actuators

Ultrasonic motor

Inchworm piezoeletric motor

University of Genoa



SHAPE MEMORY ALLOYS

Actuators SMA

ELECTROMAGNETIC FIELD 1/2

Coreless DC motors

MAGNETO AND ELECTRO-STRICTIVE FORCE

Electrostrictive actuators

Elastomeric dielectric actuators

Magnetostrictive actuators

MAGNETO- AND ELECTRO- RHEOLOGICAL EFFECT


University of Genoa



ELECTROMAGNETIC FIELD 2/2

Brushless DC motor

Micro linear motor

Stepper motor

Micro stepper motor

Solenoids

Voice coil motor


University of Genoa



FLUID ACTUATION

Bourdon pipe

Artificial muscles

THERMAL EXPANSION


University of Genoa



Index

state of art

MEMS technologies

modules design

system integration

University of Genoa



Modules design

embodiment design

commercial components

detail design

control

Improvement of arm dexterity

Target 1

University of Genoa



Design process

University of Genoa



Technical problems

Limited module size: 10 mm max (fixed by the trocar)

L 30 mm max (fixed by thorax)

Size

Machining

Operating theatre

Limited actuators power block not active joints, use light material

limited n° of modules, limited payload

Limited space available use miniature screws, gluing, welding

How to link modules together: mechanic, power, signal

High precision and accuracy is required arm stiffness, error compensation

Safety force feedback, fast module retrieval, module reliability, modules compliance

Actuation ? Material ? Transmission ? Sensors ?

Control Redundant robot control distributed logic, singularities avoidance, coordination with 2nd hand, sensor fusion, communication protocol

University of Genoa



In collaboration with:Prof. Vladimir Filaretov of Far Eastern State Technical University (Vladivostok)

Surgical articulated arm

Vladimir Filaretov Instrument design

University of Genoa



Arm with clutches

TECHNICAL PROBLEM

• Clutches are delicate

• Precision machining is needed

University of Genoa



Self powered forearmTECHNICAL PROBLEM

• Motors limit the arms power

• Low dexterity

University of Genoa



Universal joint forearmTECHNICAL PROBLEM

• Precision machining is needed

University of Genoa



Flexible joints forearm

TECHNICAL PROBLEM

• Disposition of the wires along the arm

University of Genoa



The forearms family

University of Genoa



Modules design

embodiment design


detail design

control

University of Genoa



Smoovy motor Imodel DC2S3.125.R.3size D 3.4=mm, L=13,29 mm+1,7 mm

motor speed 15000 rpm 250 rpsgear ratio 125gear speed 120 rpm 2 rpsgear torque 2,6 2,2to3,0 mNmSmoovy motor IImodel DC2S4.025.R.3size D 4.8=mm, L=16,3 mm+4,66 mm

motor speed 32500 rpm 541,666667 rpsgear ratio 25gear speed 1300 rpm 21,6666667 rpsgear torque 0,9 0,6to1,2 mNmFaulhaber motormodel 0206 Bsize D 1,9=mm, L=10,03 mm+1,55 mm

motor speed 35000 rpm 583,333333 rpsgear ratio 47gear speed 744,6808511 rpm 12,4113475 rpsgear torque 0,225 0,15to0,3 mNm

Our torque needsSewing force 0,3 Narm 4 mmSewing torque 1,2 mNm

D10

D13, A125°

4

Sewing torque

1,2 mNm

Torque needed for sewing

Actuation

Material

Transmission

Sensors

University of Genoa



Commercial miniature electric motors

COMMENTSPenn States sells miniature (1.8 mm diam, 4 mm long) piezoelectric motors too expensive (3300 Euro/each)

Piercing 0.5 N

Wire stretch 1 N

Clamp 40 N

Motor selection 1/2

Actuation

Material

Transmission

Sensors

University of Genoa



module b0 motor torque 1,493 mNm

0,357 b1 dynamic weight 0,523 mNm1,072 b2 dynamic weight 1,568 mNm1,787 b3 dynamic weight 2,614 mNm3,217 4,705

ANSWER aluminium module b can carry about 1 module b acetal module b can carry about 2 modules b

b1 b2b0

module e0 motor torque 4,805 mNm

0,831 e1 dynamic weight 1,087 mNm2,494 e2 dynamic weight 3,261 mNm4,157 e3 dynamic weight 5,434 mNm7,482 9,782

ANSWER aluminium module e can carry about 2 modules e acetal module e can carry about 2 modules e

e1 e2e0

module b0 motor torque 0,896 mNm

0,124 b1 dynamic weight 0,203 mNm0,372 b2 dynamic weight 0,61 mNm0,62 b3 dynamic weight 1,017 mNm

1,116 1,83

ANSWER aluminium module b can carry about 1 module b acetal module b can carry about 2 modules b

b1 b2b0

module e0 motor torque 2,883 mNm

0,373 e1 dynamic weight 0,522 mNm1,119 e2 dynamic weight 1,565 mNm1,865 e3 dynamic weight 2,609 mNm3,356 4,695

ANSWER aluminium module e can carry about 2 modules e acetal module e can carry about 2 modules e

e1 e2e0

alluminium 2,71 g/cm3

acetal 1,30 g/cm3

Motor selection 2/2

COMMENTPenn States piezo electric motors (1.8 mm diam, 4 mm long) are too expensive (3300 Euro/each)

Actuation

Material

Transmission

Sensors

University of Genoa



MATERIALS COMPARISON (FROM FARNELL)It is performed a comparison between the engineering materials available from Franell

density tens mod tens strength flex mod flex strength compr stength melt point Hardness elong yieldunits g/cc MPa MPa MPa MPa MPa Degrees Rockwell %

ABS 1,05 2495 41 2400 77,4 64 58 R103 2,6Acetal copolymer (Ertacetal C) 1,41 2795 62 2585 90 61 165 R120 60Acetal homopolymer (Derlin) 1,42 3105 70 2620 98 73 175 R120 30Nylon (EETALON 66 SAMU) 1,16 3645 82,5 3103 120 17 260 R118 75Nylon (EETALON 66 SA) 1,145 2238,5 72,5 1927 91,5 17 260 R116 190Nylon (EETALON 66 GF-30) 1,35 10000 190 ? 270 17 255 M100 3

PEEK 1,4 5700 110 4100 160 120 180 R130 5PTFE 2,25 489 18 600 98 12,5 327 S82 300PVC 1,46 3500 48 2534 125 ? 80 D84 120Polycarbonate (AXXIS) 1,2 2300 65 2967 100 52 154 M75 50Polyethylene (PET-P) 1,15 3200 85 3400 120 103 260 R130 20Polyethylene (UHMWPE) 0,93 606 40 517 ? ? 130 D62 350Polypropylene 0,9 1050 42 2000 45 ? 160 D80 600

Torlon 4203 PAI 1,38 4500 120 ? ? 40 357 ? 10

F

NylonLOAD ELONGATIONN mm10 < 0,01

150 mm

F

8 mm Admissible bending load

0

2

4

6

8

10

12

14

16

0,8 0,9 1 1,1 1,2 1,3 1,4 1,5

Density (g/cc)

Ad

mis

sib

le b

en

din

g L

oa

d

(N)

Any material can support about 300g as bending load

Material selection

Actuation

Material

Transmission

Sensors

University of Genoa



550 €

5 €

3300 €

8 €

4 € 18 €

Components selection

Actuation Material Transmission Sensors

Motors

90° transmission

Angular sensors

University of Genoa



Modules design

embodiment design


detail design

control

University of Genoa



Detail design

1 DOF modules

2 DOF modules

End effectors

Final solution

Index

University of Genoa



1DOF modules 1/5

OVERALL L 17.5mm (motor l 1.5mm)GEAR RATIO 0.625

TECHNICAL PROBLEM

• The face gear is not feasible

• Link between the orange gear and the pink part

• Low torque

University of Genoa



1DOF modules 2/5

TECHNICAL PROBLEM

• Multipole magnet offers low resolution

• Multipole magnet is costly

• The magnet is difficult to assemble

• Low torque

University of Genoa



1DOF modules 3/5TECHNICAL PROBLEM

• Consider undercutting for gear design

• The gear, if magnetic, is difficult to machine

• Low torque

Detail design

Given for machining

University of Genoa



1DOF modules 4/5

TECHNICAL PROBLEM

• Optic wires along the arm

• This face gear is not machinable

• Low torque

University of Genoa



1DOF modules 5/5

University of Genoa



1DOF modules family:

PROBLEM

• Low torque

• Too long

• Big gear

PROBLEM

• Low torque

• Face gear not machin.

PROBLEM

• Low torque

• Face gear

not machin. • Sensor gives low resolution

PROBLEM

• Low torque

• The magnetic gear is not machin.

PROBLEM

• Low torque

• The gear is not machin.

• Cabling problems

University of Genoa



1DOF modules: rotational 1/3

PROBLEM

• Difficult assembly

• Crown gear is not machinable

• Face gear is not machinable

• Low torque

University of Genoa




PROBLEM

• The magnetic gear is difficult to make

• The sensor is costly

• Low torque

University of Genoa




University of Genoa



1DOF modules family:

PROBLEM


• Complex assembly


• Low torque

PROBLEM

• Difficult assembly

• Crown gear is not machinable (too small)

PROBLEM



• Low torque

University of Genoa



Detail design

1 DOF modules

2 DOF modules

End effector

Final solution

Index

University of Genoa



module: length 25.6mm dexterity 124° 360°gear teeth: module 0.25mm gear ratio 8/24 (/24)

PROBLEM

• The face gears not available

• Conic gears not usable

• Where to put sensors ?

2DOF modules 1/4

University of Genoa



2DOF modules 2/4

part name massadim g1,5*part A frame 1,4699072*part B frame 0,44493962*part A motor fix 0,40098964X bearing 0,19593612X screw 0,2639524 gears 0,4894562* sensor + card 0,3766022*magnet 0,15288motor + reduction 2,26

6,0546622

University of Genoa



2DOF modules 3/4

University of Genoa



2DOF modules 4/4

University of Genoa



2DOF modules:

PROBLEM

• The face gears are difficult to find and to make.

• Conic gears give a solution mechanically not working

PROBLEM

• Too long

University of Genoa



Detail design

1 DOF modules

2 DOF modules

End effector

Final solution

Index

University of Genoa



Clamp 1/2

6,8

7

7,2

7,4

7,6

7,8

8

8,2

0 5 10 15 20 25

angle (degrees)

HPL0(6 mm), L1(6,95 mm), , F1

F3=F1cosL3=L5*F3/F1 (L3/F3=L5/F1)L5=L6+L1L1=6,95 mmL6=L0*tg (tg=L6/L0)

M=L3*F3

M=L3*F3=(L5*F3/F1)*(F1cos)=L5*F3*cos=L5*F1*(cos) 2̂=L5=L6+L1=LO*tg+L1

M=(LO*tg+L1)*F1*(cos) 2̂

L3=M/F3=M/(F1*cos)

F1F3L3

L1

L2

L5

L6

L4

L0ACTUATION Smoovy 5mm + Harmonic drive 1:500

OVERALL LENGTH

31,4 + 5,6 mm

POWER 58 N (optimistic)

PROBLEM

• Too Long

University of Genoa



Clamp 2/2

SMA

actuated clamp

University of Genoa



Clamps family:

PROBLEM

• too much SMA elongation is needed

PROBLEM

• assembly

PROBLEM

• too long

PROBLEM

• we need a long module

PROBLEM

• not much place for the wires

PROBLEM

• force and elongation not along the axis

PROBLEM

• assembly

University of Genoa



End effectors family

PROBLEM

• High clamping force is required

• Friction between clamps and needle is low

• Final module needs to be short

PROBLEM

• Integrate into the system position and force sensors

• Control the blade advance

• See exactly were the instrument is cutting

PROBLEM

• Throw out the sewing wire from the spiral

• To tension the sewing wire

• To knot the sewing wire

PROBLEM

• Fix the instrument respect to the organ

• Assembly is complex

• Rotation of the syringe needle

University of Genoa



Sewing instrument

TECHNICAL PROBLEM

• Wire tensioning during sewing

• Creation of knot

University of Genoa



Detail design

1 DOF modules

2 DOF modules

End effector

Final solution

Index

University of Genoa



Modules selection

University of Genoa



Final solution 1/4

University of Genoa



Final solution 2/4

University of Genoa



Final solution 3/4

University of Genoa



Piercing 0.5 N

Wire stretch 1 N

Clamp 40 N

Final solution 4/4

A B

University of Genoa



Index

state of art

MEMS technologies

modules design

system integration

University of Genoa



System integration

architecture selection

workspace

simulation

evaluation Selection of a robotic platform able to carry the arm

Target 2

University of Genoa



PROBLEM

• production cost and weight

• the device is cumbersome

Reduce the size of the surgery platform

Patient

Arm carrier 1: industrial robot

University of Genoa



PROBLEM

• the device can exert limited force

• the instrument is delicate

Zemiti Nabil

PhD project

Minimise motors outside the patient

Patient

Arm carrier 2: miniature robot

University of Genoa



PROBLEM

• the device can exert limited force

• the instrument is delicate

Patient

The tendence is to ‘push’ as many DoFs as possible inside the robot

Arm carrier 3: snail

Preferred solution

University of Genoa



Module length

Optimal N of DOFs

Insertion problem

Multiple solutions

Device syntesis

Snail architecture

University of Genoa



Snail 3D view

University of Genoa



System integration


kinematics

simulation

evaluation Analysis of the robot workspace and singularities

Target 3

University of Genoa



Workspace, singularities and control

Forward kinematics Singularity analysis Backward kinematics Robot dynamics

Denavit Hartenberg

---

Robot workspace

---

Maple parametric algorithm

Graphic method:

screw theory

---

Analytic method:

Plücker coordinates

Velocity transform matrix

---

Maple parametric module

Database graphical output

Reduction to polynomial method

---

Pieper’s method

---

Numerical method

Creation of C++ simulation environment (on ODE language)

---

motion strategy

University of Genoa



Forward kinematics

ROBOT ARCHITECTURE GEOMETRY PARAMETERS: L1, L2, L3, L4

JOINT COORDINATES: 1, 2, … 6

JOINT RANGES: 1min<1<1max …..

DENAVIT HARTEMBERG

PLUCKER COORDINATES

TRANSFORMATION MATRIX

VELOCITY TRANSFORM

MATRIX

- END EFFECTOR POSITION: X, Y, Z - END EFFECTOR ORIENTATION: R - SINGULARITY CHECK: DET(Tc)

University of Genoa



Denavit Hartemberg formulation

6 DOF arm

Redundant arm

University of Genoa



Instrument workspace: Denavit Hartenberg

GEOMETRICAL DATA OF THE ARM

JOINT COORDINATES RANGES

WORKSPACE ANALYSIS

MAPLE

DIRECT KINEMATIC MODEL OF THE ARM ARCHITECTURE

DH

POSES OF THE END EFFECTOR

ARM CONFIGURATION

3D VISUALIZATION

GRAPHICAL OUTPUT

POINT CLOUD

Forward kinematic

University of Genoa



Instrument singularities: screw theory

The mini-arm is a decoupled manipulator. The configuration is singular if one of the following conditions is satisfied:

University of Genoa



Instrument singularities: velocity transform matrix

GEOMETRICAL DATA OF THE ARM

JOINT COORDINATES RANGES

SINGULARITY ANALYSIS

MAPLE

TRANSFORM MATRIX OF THE ARM ARCHITECTURE

SCREW THEORY

SINGULAR POSES OF THE END EFFECTOR

JOINTS VELOCITY

3D VISUALIZATION

GRAPHICAL OUTPUT

POINT CLOUD ARM WORKING CRITERIA

Velocity transform matrix Tc

Determinant of Tc

Solutions

University of Genoa



Instrument singularities: iso-orientation surfaces

Screw theory

University of Genoa



Instrument singularities: overall view

Screw theory

University of Genoa



1) Database creation by numerical analysis

2) Singularities workspace database query

Instrument singularities: database query

University of Genoa



System integration


workspace

simulation

evaluation Control of the redundant surgical robot

Target 4

University of Genoa



Distributed control strategy

MISSION PERFORMING

TASK REQUIREMENT END EFFECTOR POSITION AND FORCE

MODEL BASED CONTROL INVERSE KINEMATICS SINGULARITIES AVOIDANCE NON LINEARITIES COMPENSATION

PID CONTROL MODULE 1 END EFFECTOR POSITION AND FORCE


………..


BODY ENVIRONMENT

University of Genoa



The control of the surgery robot is implemented (450 lines of code) using the ODE library

Inverse dynamics

Real-time control

Obstacle avoidance

Control of the snail surgery platform

TROCAR

University of Genoa



Path planning strategy

University of Genoa



Sensor fusion

University of Genoa



Arms cooperation

From 3 to 4 endoscopic arms are necessary to complete a minimally invasive surgery operation

University of Genoa



System integration


workspace

simulation

evaluation Evaluation of the prototype performance

Target 5

University of Genoa



Proposed arm modules

University of Genoa



Selection of modules prototypes

University of Genoa



Damien Sallè Genetic arm optimisation Prototype design, assembly

Prototypes: single module

University of Genoa



Actuation detail

University of Genoa



Torque measurement

Speed 72 °/s

Couple 5.8 mNm

Spam ± 104°

79 g

University of Genoa




2 DOF module

University of Genoa



Gripper I actuation

University of Genoa




Gripper I performance

Clamping force

40 N

University of Genoa



Gripper II overall view

Filippo Morra Gripper design

University of Genoa



Jaw and spring

Filippo Morra Gripper design

Gripper II actuation

University of Genoa



Vision

Sergio Daprati Gripper design

University of Genoa




Arm prototype

Piercing 0.5 N

Wire stretch 1 N

Clamp 40 N

Length 120 mm

N° of DoF 5 (inside)

Weight 20 g

University of Genoa



Snail joint detail

University of Genoa



Surgery arm prototype performance

LRP Lab, Univ. of Paris 6

PMAR Lab, Univ. of Genoa

University of Genoa



System integration

Silvia Frumento back-arm design

University of Genoa



• A concept for an agile modular surgical robot is presented and studied

• Several possible modules have been designed, some prototyped and tested with satisfactory results

• A strategy for effective operation of the robot is outlined and tested in simulation

Conclusion

University of Genoa PMAR – Department of Mechanics and Machines design Development of micro-tools...

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Transcript of University of Genoa PMAR – Department of Mechanics and Machines design Development of micro-tools...