Grasp and Force Based Taxonomy of Split-Hook Prosthetic Terminal Devices

Joseph T. Belter, Bo C. Reynolds, and Aaron M. Dollar, IEEE Senior Member

Abstract — In this paper, we analyze the use of the body-powered split-hook prosthetic terminal device, which is the most commonly used upper-limb prosthesis. We developed two taxonomies of split-hook use, one on grasp shape and one on force exertion, illustrating the functional capabilities and use cases of the device. Video captured from an amputee using a body-powered split-hook during a number of common activities was used to lend weight to the completeness of the classifications. These taxonomies serve to establish a common language and means of comparing the types of grasps achievable by simple terminal devices to those of advanced myoelectric terminal devices or even human hands. The first taxonomy categorizes the grasp type based on the contacts with the environment while the second is categorized by the method and limitation of force exertion. We discuss the difference between grasps capable of holding objects compared to those that are capable of acquiring objects and the importance of non-prehensile uses of the split-hook. The classification schemes lay the groundwork for further detailed study of split-hook use, and the discussion of the use cases described may help guide terminal device developers to create improved prostheses.

Keywords—split-hook; terminal device; prosthetic hand

I. INTRODUCTION

Although hundreds of prosthetic terminal devices are available, ranging from task specific devices to almost indiscernible cosmetic replicas of human hands [1], the voluntary opening split-hook (shown in Fig. 1) is widely accepted as the most commonly utilized functional terminal device [2]. Even with advanced multi-fingered and multi-DOF myoelectric terminal devices now available on the market, many prosthetists and amputees still turn to the body-powered split-hook due to its proven robustness, performance, low cost, and light weight [3], and many amputees who have learned to utilize the split hook without any major difficulties are reluctant to switch to a newer technology with a long learning curve.

Researchers have long categorized and organized human hand grasp types to better understand and emulate the capabilities of human manipulation. An early taxonomy divides human grasps into six main categories: cylindrical, tip, hook, palmer, spherical, and lateral based on the approximate shape of the hand while grasping an object [4].

This was later extended to a more complex human hand grasp taxonomy by Cutkosky based on the grasp types required in a manufacturing environment [5]. Manipulation taxonomies have also been proposed that classify the relative motion between the object and hand rather than the “shape” of the grasp [6]. The information on human hand use is commonly collected through observation and through the analysis of film collected in a natural use setting. A recent study by Zheng et al. analyzed video footage of human hand use taken during non-structured tasks for machinists and housemaids [7]. By recording each grasping task, the relative distribution of grasp types was measured.

In this paper, we present two sub-classifications of split-hook prosthesis use to enable a better understanding of the functional capabilities and usage of this class of terminal devices. While the specific pose or shape of the hook with relation to the object may help to define the grasp type, it was also observed that within different grasp types there are multiple limitations to the forces that can be exerted on the object. For this reason, we separated our look at the split-hook into two taxonomies. The first is based on the nature of contact with an object, while the second is based on the types of force exertion that can be utilized.

There has been relatively little work related to thorough classifications of split-hook usage that focuses on the function of the device instead of the task. While the majority of studies on prosthesis use to date has primarily involved written surveys of users (e.g. [8]), others have supplemented with follow up visits to the amputee’s home to observe the use of the device in the normal and unstructured environment [9]. As far as the authors are aware, all of these studies focus on high-level function (e.g. usage frequency, classes of tasks) without detail on the specific ways in which the device is used. The most relevant study that we were able to identify was performed by Fraser in 1998, in which 66 amputees were videotaped at their homes using their terminal device while performing a set of common tasks [10]. The video was then analyzed and each action involving the terminal device was categorized into a manipulative or non-manipulative category. The secondary categories included, grip, release, hold, transfer, support, steady, etc. While generally a very thorough study, it did not focus on specifics of the device usage and the categorization was broad enough to cover the wide range of devices used, including purely cosmetic terminal devices.

This work was supported in part by the Gustavus and Louise PfeifferResearch Foundation.

J. T. Belter, B. C. Reynolds, and A. M. Dollar are with the department of Mechanical Engineering and Material Science, Yale University, NewHaven CT 06511, USA (email: joseph.belter@yale.edu, bo.reynolds@yale.edu, and Aaron.dollar@yale.edu)

978-1-4244-7929-0/14/$26.00 ©2014 IEEE 6613

tysimsdtainud

A

th1th[

tiFNfmfgcgcnthgAth

toacsthlc

We are inteype terminal d

specific desigmproved, and

scheme. We bdesign of the saxonomies. Wncluding ways

utilize it to imdesigns.

A. Description

The split-hohe original pa

1912 [11]. Desphe most popul2].

In the most itanium or stai

Fig. 1). The inNitrile or Neofriction and prmetal hooks. Tfeature (sometigrasp slender, lcigarette. At thgrip surfaces ccutout in the naturally centerhe wrist. The i

gripping surfacAlso, the clamphe contact poin

The top fingeo the plane of

and supports tcontrol cable asimilar to the whe back side ength of the

control cable a

Figure 1. Standarand the method of

erested in studydevice usage w

gn shortcomintherefore wou

begin this papesplit hook and

We then presens to extend it tomprove and

II. M

n of Split-Hook

ook terminal datent was awarpite its crude alar terminal de

basic form, tinless steel fingnside of the finoprene grip marevent objects The grip matimes called thlong cylindrica

he base of the called the clam

center to prr cylindrical obintended purpoce on anotherp can provide nts are closer toer has a long fethe finger. Thi

the attachmentand serves as way the humanof a pencil (sthumb determ

about the hinge

rd features of the bf operating the hoo

ying the specifwith enough d

ngs and areauld like a detaier with a detad methods usednt and discuss o other devicerefine future

METHODS

k

device has charded to David aesthetic appeaevice for uppe

the split hook gers shaped to ngers is coatedaterial to incr

from being sterial has an e “cigarette noal objects simifingers there a

mp. These platovide additionbjects along anose of the clamr plane to thata much largero the pivot poieature protrudiis feature is cat point for th

a contact pon thumb base asee Fig 1, cen

mines the mome at the base o

body powered splitok using a body-po

fics of split-hodetail to identas that can led classificatiailed look at td to develop tthe taxonomi

e types as well terminal devi

anged little sinW. Dorrance

arance, it remaier limb ampute

consists of twform a hook (s

d with a layer rease the surfascratched by tadditional bulotch”) that hellar to a pencil are two opposites have a smnal support a

n axis in line wmp is to provide

t of the finger grip force sinnt of the devicing perpendicualled the “thumhe body-poweroint for graspiand palm suppnter image). Tment arm of tof the fingers.

t-hook terminal deowered control cab

ook ify be

ion the the es, as

ice

nce in

ins ees

wo see of

ace the lge lps or

ing mall and

with e a ers. nce e.

ular mb” red ing ort

The the In

the vol1, the felastic usuallyuser’s elastic strengthan objeto havinfatigue

The weight split-hograms fthe simabout eWhen mfingers importahands.Dorransplit-hodifferendesign results,

B. Ter

In othat wil

evice. Here, the thble.

luntary-openingfingers are conbands. A pul

y accomplishedshoulders or ubands and o

h of the elasticect when it is bng a higher nuassociated witmajor benefitsand durability

ook weighs onfor modern my

mple metal conenvironmental manipulating sdoes not obst

ant factor whWhile we fo

nce 5x style hooook type tences such as la

features may, as described l

rminology

order to removell be used withPrehensile –supported wirequirement oContact – Podevice and thGrip Securityexternal distuExternal Forworld that wothe terminal include pushiInternal Forcfingers of theinclude pincfashion.

hree views show th

g style terminanstantly being ll of the bodyd through rel

upper arm, oveopens the finc band determbeing gripped umber of elasticth pulling the cs of the split hy. The standar

nly 213 grams yoelectric handnstruction userfactors such a

smaller objecttruct the view

hen comparingocus the taxooks, the resultserminal deviack of the “thuy require sliglater.

e ambiguity, whin the taxonom– The object ithin the termof gravity to hooint of interactie object or envy – Ability to urbances applierce – A force ould require adevice. These

ing, pulling, or ce – A force the terminal deviching and gra

he classic Hosmer

al device, as sheld together

y-powered conlative movemeercomes the fongers. The nu

mines the forcein the device. c bands is the control cable. hook are attribrd Hosmer Doas compared t

ds [12]. Also, rs do not needas heat and abts, the thin proof the object.

g hooks withonomies on ths apply to mostices. Howevumb” or additioht modificatio

we have definedmy. is intended to

minal device wold the object inion between thvironment.

maintain the ed to the object applied to th

an equal force e types of lolifting.

hat is created bce. These typeasping in a

Dorrance 5XTi ho

een in Fig. by a set of

ntrol cable, ent of the orce of the umber and e placed on

A tradeoff increase in

buted to its orrance 5X to 400-600 because of d to worry brasion [2]. ofile of the

This is an functional

he Hosmer t classes of

ver, small onal finger ons to the

d the terms

o be fully without the n place. he terminal

grasp with t. he external to support ads would

between the es of forces

prehensile

ook shape

6614

C

dupfncsiwruvvgdainr

A

thfpmnloaintyapimhty

C. Method of E

The presentediscussions betuser of a Hosmpowered split-footage was anumerous acticooking/eating shows four sams being used to

was gathered recording systeuser was recorvideo data wavalidate the taxgrasp or interadeveloped claadditional categn Fig. 3 and

recorded video

A. Grasp-base

The grasp taxhe split-hook i

first divided prehensile catmanipulative anon-prehensile ocations of co

all surfaces of nner surface wypes of interac

and often in presentations omportant aspe

hook and the sype interactionThe prehensi

Figure 2. Videounilateral body-po

Establishing Ta

ed taxonomies tween the auth

mer Dorrance 5-hook. In addacquired of thivities, includmeals, and sta

mple frames froo accomplish susing a head

em similar to trded while in as studied by xonomies, withaction seen inassification scgories were reFig. 4 are ba

.

III.

ed Split-hook T

xonomy (Fig. 3is used to intethe interactiotegory, in a

and manipulativcategory w

ontact on the hthe hook inclu

were used in a ctions were use

assistance to of terminal devcts are often oshape help it ns more predictile category i

o frames showing owered split-hook

axonomies

were generatehors, one of whX-Ti, voluntar

dition, over 5 hat author’s hding hygienic andard office som the video insimple tasks. T

mounted webthe system usehis natural hoall the autho

h the authors cn the video achemes to equired. The ex

ased on those

RESULTS

Taxonomy

3) attempts to ract with the ens into a no

similar wayve category us

was then subdhook. It was shuding the tip, f

non-prehensiled to provide st

the able havice grasping coverlooked. Thto perform thtably. is first sub-di

different grasp tuser.

ed after thorouhich is a 10-yery-opening bod

hours of vidhook use duri

tasks, laundstyle work. Fign which the ho

The video footabcam and vid

ed in [7], and tome setting. Thors and used categorizing eaaccording to tensure that xamples depict

seen within t

capture any wenvironment. Won-prehensile y to the nosed by [10]. Tdivided by thown that almofront, thumb, ale manner. Thetabilizing actio

and. In standacapabilities, thehe rigidity of te non-prehens

ivided based

types exhibited by

ugh ear dy-deo ing

dry, g. 2 ook age deo the his to

ach the no ted the

way We

or on-The the ost

and ese ons ard ese the sile

on

whethemain pwith ththe “finwithin occurribased osplit-ho“precislong, than addiwhere ain contcombinorganizgrasp scontact

Note in Fig. contralacomplethese gwith retrying tFor exahold apositionwithout

B. For

The sdifferenenvironexertionvery simfunctioThe selimits environsystem,

The used toprosthetradeofattacheduring loads wthe user

The ihook anumberaccordialso bepowereis graspthe mabands, size of

y a

er the fingers aprehensile featuhe outer surfacenger/exterior” the “clamp”.

ing between thon the number ook. These aresion grasps” onhin objects, anitional feature a large portiontact with the

nation with thzed from left tsecurity which ts between the that a few par3, typically caateral hand or

exity and the ggrasps generallespect to the spto pick up an ample, the coman eating orning of the utt placing it in t

rce-based Split

split-hook forcnt methods annment. The fin based on extmilar to the di

ons since all precond sub-catethe amount o

nment. This , the elastic bansuspension sy

o fixate the pretic socket anff exists betwed and the lev

pushing, pullinwithin this cater. internal grippinare generally r and stiffnesing to their pree modulated bed control cableped and all tenaximum force the location o

f the object. F

are used. Althure of the splie of the fingergrasp, with a For prehensi

he fingers, theyof contacts be

e limited to twn small objects)nd often involvsuch as the “th

n of the entire gobject, which

he “clamp”. Tto right based is strongly corhook and the o

rticular grasps,annot be achievr terminal devgeometry of thly require propplit-hook and wobject directly

mmon “Thumbr writing utetensil that is nthe grip using t

t-hook Taxonom

e exertion taxond limitation irst categorizatternal or internivision of nonrehensile graspegorization is bof force that

includes the ands, and the coystem consists rosthesis to thend body powween how tigvel of comfortng, or lifting is

egory are also l

ng forces of thdetermined by

ss of which aeferences, needby a balance e and the elast

nsion is releaseexertion is d

of the object wFor a standard

hough the fingit-hook, graspis was also obsroll of tape),

ile grasps wity were again setween the objwo contacts (u), four contactsving both the fhumb”), or aregrip material sh is sometimeThe entire taxon an increasrrelated to the object. , marked with ved without thevice. Partly duhe objects useper position ofwere not achievy from a table b/Fingers” grasensil, requirenot generally the other limb.

my

onomy (Fig. 4)of exerting lotion separatesal forces. This

n-prehensile or ps require interbased on the can be exert prosthesis ontrol cable.

of the entiree amputee, incwered harnessghtly the pro, the amount s limited. The limited by the

e voluntary-opy the elastic bare chosen byds, and abilitieof tension in ic bands. When

ed from the condependent on within the hoo

amount of el

ers are the ing objects served (e.g.

as well as th contacts sub-divided ect and the usually for s (often for fingers and ea contacts, surface was es used in xonomy is e in object number of

an asterisk e use of the ue to their ed in them, f the object vable when or drawer. sp, used to s specific achievable

) shows the oad on the s the force

division is prehensile

rnal forces. factor that

ted on the suspension

e apparatus cluding the s. Since a osthesis is of loading achievable strength of

pening split bands (the y the user es), but can

the body-n an object ntrol cable, the elastic

ok, and the lastic band

6615

t1incalothcthb

rffadtcs(cm

ension, the gri1-3 cm sized on the clamp ca

crushing a peaalso overpoweroad with the ohis type of gra

cable, minus thhe elastic band

band. Often more d

required. In thforce on the cforce is placedalone. Ultimatedifference betwension stored

concentration, tsmall spring, o(far right). Hocable, it can bemoving their a

Figure 3. The Splharness. *Grasps

ip force at the objects. The grian reach 140 Nanut within ther the strength ooutside of the asp is the tensiohe force requirds, as shown in

delicate and finhis case, the ucontrol cable sd on the objectely, the grip foween the loadin the elastic the user is ableor a compliantowever, due toe difficult for tharm in space.

it-Hook grasp taxoonly observed by p

fingers is betwip force of a 1

N. In Fig. 4, the clamp featurof the elastic bfingers. The l

on in the body red to open th

n Fig. 4 separat

ne movements ouser can alter such that a mut than that of trce exerted on

d in the controbands. With a

e to grasp delict drink lid, as o the requiredhe user to keepThe force-bas

onomy shows all oplacing the object

ween 45-70 N f cm sized obje

he hook is showre. The user cbands and exerlimiting factor powered contr

he fingers due ting a stiff rubb

of the fingers athe position auch smaller grthe elastic ban

n the object is tol cable and ta high degree cate objects likeshown in Fig

d tension on tp that pose whsed taxonomy

observed uses for twithin the hook u

for ect wn can rt a

in rol to

ber

are and rip

nds the the of

e a . 4 the

hile is

sorted require

The tthe spliinteractbased oachievacommoof achiorientatintende

A. Obj

A mdifferentype. SpreposiFor exaFig. 2 (hand pomost gr

the voluntary-openusing the able hand

from left to ried to perform e

two taxonomieit-hook is usedtion types. Alon the objects able prehensilon object sizes ievable grasp tions, dependi

ed to be perform

ject Acquisition

major feature nce in acquisit

Some of the gritioning of theample, the four(bottom) securositions the forasp types invo

ning split-hook as d.

ight by the leveach category o

IV. DISCUSS

es presented ind to perform a lthough the gbeing grasped

le grasps ecoand geometrietypes hold m

ing on the remed.

n versus Holdi

of grasp uttion methods frasps are unace object prior tur-contact, thumring a fork, is rk within the holving multiple

controlled by a bo

vel of user conof force exertio

SION

n Fig. 3 and 4 wide array of

grasp taxonomd, it can be seompass a lares. Furthermore

many objects iequirements o

ing

tilization relatfor each partic

chievable withoto closing the mb/finger grip,only achieved hook. This is the contacts with

ody-powered contr

ncentration on.

4 show that f grasp and

my was not en that the

rge set of e, the array in multiple of the task

tes to the cular grasp out careful split-hook. , as seen in if the able

he case for h the thumb

rol cable and

6616

ohthowbpdsopd

andowSatehthc

B

hmthptyvacin

or clamp. Prephand manipulahe object befo

object into a mwithin hand mabe placed in thplaces a large ddevice for mucshows that not of acquiring ipractical usagedoing unilatera

The necessitya useful grasp non-prehensile devices. In factof the split-howithin-finger tSimilar results amputee requirerminal device

easier to simplhand. Perhaps shis additiona

concentration, t

B. Modificatio

Designers hahook design anmethods [1]. Whe hook could

presented in thypes including

voluntary closappropriately ncylindrical opentended to gra

Figure 4. The spthe maximum for

osition of objetion when oneore within-han

more stable or anipulation in he hook in thedemand on thech of the pract

only is the grit in order to e to both unill and bilateral

y for careful prposition may uses of the

t, the most comook user weretwo-contact gr

were found bres the use oe in holding or ly perform the since non-prehal effort andthey are perfor

ons of Hooks/ N

ave seen limitnd proposed al

We can easily d expand, or

his paper. Fig. g the “Work Hing hook (rignamed based ening between sp the handle o

plit-hook force taxrce exerted and the

ects is observee grasp type isnd manipulatio

useful grasp. the split-hook

e exact positioe contralateral ical function orasp important

determine itlateral and bitasks. repositioning p

lead to the hsplit-hook or

mmon grasps se non-prehensrasps the nextby Fraser [10f the able hausing an objectask complete

hensile functiond require vrmed more freq

New Hook Desi

ations to the lternative featusee how the ffill in, the g5 shows two

Hook” (middleght) [1]. The

on the additithe fingers. T

of a broom or s

xonomy shows thee amount of user c

ed in able hums used to pick on transitions tWith the lack , the object mu

on for use whihand or termin

of the hook. Tht, but the meths relevance alateral ampute

prior to achievihigh incidence r other terminseen in the vidsile grasps, wt most commo]. If a unilate

and to assist tct, then it may ely with the abns do not requ

very little usquently.

igns

traditional splures or actuatifeatures added rasp taxonomadditional ho

e) and the Sierwork hook w

ion of the larThis opening wshovel. When w

e methods of forceconcentration requi

man up the of

ust ich nal his

hod and ees

ing of

nal deo

with on. eral the be

ble uire ser

lit-ion

to ies

ook rra

was rge

was we

look at a moregrasp ty

Whillimitatirobust m“wrap betweepower hands,standarmade uoften saor prost

Whensplit-honature importaobject the devcould bpowereneed tovoluntaoffer ththe hooas deschook incontrolcumber

In adnumeroThese space particulrod [1].

e exertion utilized ired to achieve tha

t the grasp taxoe robust alternype. le the work hion to the capamedium and lagrasps” as the

en grasper andgrasps make uyet are not c

rd split-hook. up for by utilizandwiching larthesis socket an looking at took, it is clear of any voluntant of which than the limitavice were a vbe directly sp

ed cable. One o be maintaineary closing hohe ability to exok. The voluntacribed above buin position whl cable (althoursome and somddition to thesous task speciftypes of devicof required glar aspect such.

by split-hook userat particular task.

onomy in Fig. native to the

hook partially abilities of the sarge diameter pey involve a

d object to supup a large portcapable of beiThe lack of azing the split-rge cylindrical

and their chest the force exethat there are

tary opening teis the inabilityation imposedvoluntary clospecified by th

drawback is ed while holdiook lacks the xert larger forary-closing oput also featureshen the tensiough this lockin

metimes unreliase changes in fic hook-type tces do not attgrasp types, h as holding a

rs. The organizatio

3, we see thatfour-contact f

addresses it, split hook is thpower grasp (olarge amount

pport large loation of grasps ing performeda large power -hook wearer’sl items betweeor stomach. rtion capabilitlimitations ba

erminal devicey to close tigh

d by the elasticsing split-hookhe tension in that this tens

ng an object. clamp feature

ces within theeration gives ts a lock that won is releasedng feature can

able). the split hoo

terminal devicetempt to span but focus sobaseball glove

on is based on the

t this offers finger-span

one major he lack of a often called

of contact ads). These for human

d using the grasp was

s body and en the hook

ties of the ased on the e, the most hter on an c bands. If k, the load

the body sion would The Sierra e but does e fingers of the benefits ill hold the

d from the n be a bit

ok designs, es are sold.

the entire olely on a e or fishing

limitation to

6617

fptotohothafcwimoo[cwnosaginpr

P

[

[2

[3

V.

Using the splfunctional use prostheic hand o perform a wo acquire all

hand and the aof the voluntarhe presented ta

analysis in orfunction of numclassified the twe would likmportance of e

or the types of others. This an5,6,7], but non

classified and rwould like to enumber of subjof grasp typestatistical distriadd an additiongrasp listed in nformative de

prosthetic handrequired by the

The authorsPfeiffer Resear

1] RSL Steeper 2009. http://bebioni_limb_catalog

2] C.M. Fryer, JComponents”RehabilitationSurgeons, edi

3] G. H, Kejlaprotheses to u163, 1993

Figure 5. Basic (middle) and the S

CONCLUSION

it-hook taxonoof the hook wuse. Although

ide variety of the grasps wit

ability to exert ry opening conaxonomies cander to compamerous terminypes of grasps

ke to get a each grasp typegrasped objec

nalysis has been-prehensile furecorded. To dextend our vidjects and taskse and duratioibution of grasnal element relthe taxonomy

ecision makingds depending o end user.

ACKNOW

s would like to ch Foundation

REFER

“Upper Limb ProRetrieved

ic.com/uploads/filegue.pdf J.W. Michael, “U” Atlas of Limb Pn Principles, Ch. 6ition 2, 1992, repri

aa, “Consumer coupper limb ampute

Hosmer 5X hookSierra Hook (right)

NS AND FUTURE

omy, we can eaith both humanh the split-hoofunctions, it lathout assistancforces is limit

ntrol strategy. n allow for moare and betternal devices. Als achievable bbetter unders

e based on the ts that are mor

en performed functions of the do so with termdeo analysis fos, as well as toon to enable sp type utilizatlated to the imand therefore

g process for on the usage a

WLEDGMENTS

thank the Gusn for supporting

RENCES osthetic Componen

Jan es/upper

pper-Limb ProsthProsthetics: Surgi6A, American Acinted 2002 oncerns and the ees,” Prosthet Orth

k (left) compared t) [1].

E WORK

asily compare tn hand and oth

ok has the abilacks in the abilce from the abted by the natuWe believe th

ore detailed grar understand tlthough we hay the split-hoostanding of tfrequency of u

re important thfor able hands hand were rare

minal devices, wr a much grea

o include loggicalculations

tion. This woumportance of ea

allow for a mothe designer

and functional

tavus and Loug this work.

nts Catalogue” 202013 fr

hetics: Body-Poweical, Prosthetic, aademy of Orthope

functional value hot Int, vol.7, p. 1

to the “Work Hoo

the her lity lity ble ure hat asp the ave ok, the use han

in ely we

ater ing of

uld ach ore of

lity

ise

08-rom

ered and edic

of 57-

[4] G. in EGer

[5] M.RHan(19

[6] I.MClaTra

[7] J.ZGraTas9-1

[8] C. PmyDec

[9] A. Zuiamp

[10] C.MfunOrt

[11] D.W191

[12] J.TDesProDev

ok”

Schlesinger, “DerErsatzglieder und rmany: Springer, 1R. Cutkosky, “On nds for Manufactu

989) 269-279. M. Bullock, R.Rassification of Humansactions on Hapt. Zheng, S. De Lasp Type and Fresks” Int. Conf. on 3, 2011. Pylatiuk, S. Schul

yoelectric prosthetic. 2007 Van Lunteren, GHithoff, “A field putees” Prosthet O

M. Fraser, “An enctional prosthesesthot Int, 22:216, 19W. Dorrance, “Ar12 . Belter, J. Segil,sign and Perfo

osthetic Hands” velopment, Aug. 2

r Mechanische AuArbeitshilfen, M

1919. n Grasp Choice, Gruring Tasks,” IEEE

R. Ma, and A.Muman and Robot Dtics, 2013 vol. 6(3

La Rosa, and A.Mequency in Daily Robotics and Auto

lz, L. Doderlein, “Ric hand users” Pro

HM Van Lunterenevaluation of a

Orthot Int. 7, 141-evaluation of thes by unilateral up998 rtificial Hand”, U

A.M. Dollar, anormance Specific

Journal of R2013 50(5):599-61

ufbau der Kunstlic. Borchardt et al.

rasp Models, and E Trans. Robot. A

M. Dollar “A Dexterous Manipu), pp. 129-308.

M. Dollar “An InvHousehold and Momation, Shanghai

Results of an Interosthet Orthot Int.,

n Gerritsen, H.G. arm prostheses f-151, 1983 e use made of c

upper limb amput

US Patent #1,042,4

nd R.F. Weir “Thecations of AnthRehabilitation Re18

hen Glieder,” , Eds. Berlin,

the Design of Automat., 5(3),

Hand-Centric ulation” IEEE

vestigation of Machine Shop i, China, May

rnet survey of 31(4):362-70

Stassen, M.J. for unilateral

cosmetic and ees” Prosthet

413. Oct. 29,

e Mechanical hropomorphic esearch and

6618