Archived version Author manuscript: the content is identical to the content of the published paper, but without the final typesetting by the publisher

Citation/Reference Billiet L., Van Huffel S., (2016),

Activity Recognition for Physical Therapy: Moving to the Home Environment.

Belgian National Day of Biomedical Engineering, November 25, Brussels, Belgium.

Archived version Author manuscript: the content is identical to the content of the published paper, but without the final typesetting by the publisher

Published version NA

Journal homepage http://www.ncbme.ugent.be/event.php?id=71

Author contact lieven.billiet@esat.kuleuven,be + 32 (0)16327685

IR NA

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B elg ian Da y o n B io m ed ic al E n g in ee ri n g No v e m b er 2 5 , 2 0 1 6

A C T IVI TY REC O G NITI O N F O R PHY SIC A L THE R A PY MOVIN G T O TH E HOME E NVI R O NME N T Li e v e n B ill iet

, S a bi ne V an Huf fel

K U L eu v en , S tad ius Ce nte r f or D y na m ic al S y s tem s , S ign a l P roc es s ing a nd Data A na ly ti c s , B el gi um

iM ind s Me d ic al IT , L eu v en , B e lgi um K e y wor d( s ): bi os ig na ls 1. INT RO DUCT IO N In ph y s ic al the rap y , the the rap is t is of ten inte res ted i n the f un c ti on al c ap ac it y of the pa ti e nt i.e. th e ab ili ty to pe rf o rm a c ertai n tas k . No w ad a y s , th is is as s es s ed us ing a p ati en t- rep orted (h en c e s ub jec ti v e ) qu es ti o nn a ir e s u c h as the B ath A nk y los is S po nd y lit is F un c ti on a l Ind ex (B A S F I) [2 ]. T he qu es ti o nn a ir e lis ts tr an s itor y ac ti v iti es us ed in the ra p y . B ef ore or af ter pe rf or m ing the ex e rc is es in a th erap y s es s ion , the pa ti en t s c ores hi s or he r ab ili ty to pe rf or m i t. Ho w e v er, the se ac ti v iti es are ty p ic al ly a ls o pe rf or m ed in the ho m e en v ir on m en t, ev e n as pa rt of da ily lif e. A s a fi rs t s tep tow ards the as s es s m en t of f un c ti on a l c ap ac it y at ho m e, the rel e v an t ac ti v it ies s ho u ld be rec og ni z e d. S ec on dl y , th e y s ho u ld b e a s s es s ed ob jec ti v el y i n an int erpr eta bl e w a y , as an al ternat iv e to th e c urr en t s ub jec ti v e ev al u ati on . T hi s w ork f oc us es on th e f ir s t a s pe c t. A c c el erom etr y ha s be en us ed ex ten s iv el y for ac ti v it y r ec og n it ion [ 1 ]. Y et, i t m os tl y f oc us es on rec og ni ti o n of r ep eti ti v e ac ti v it ies or po s es ( e.g . wal k ing , s itti ng ), whereas the tr a ns it ion s are m ore i nf or m ati v e in ph y s ic a l th erap y . 2. M A T E RI A L S A N D M E T HO DS 28 pa ti en ts s uf ferin g fr o m ax ial s po nd y loa rthri ti s wer e e qu ipp ed wi th a S en s e W ea r A rm ba nd ( 2 - ax ial ac c el erom ete r s am pl ing a t 32 H z ). It was m ou nte d at the up p er (do m ina nt) ar m to c ap ture bo th ful l- bo d y a nd p erip he ral m ov em en t. T he n, the pa ti e nts pe rf or m ed a s erie s of ten ac ti v it ies de ri v ed fr om the B A S F I q ue s ti on na ir e , s up erv is ed b y a p h y s ic al t h erapi s t. T he ac ti v iti es inc lu de d e.g . s it -to -s tan d, m a x im al r ea c h, g ett ing up, ly ing do wn a nd pi c k ing up a pe n ( F igu re 1 ). Rec og n iti on of the s e a c ti v iti es is ac hi ev ed throug h a t wo -s tep ap pr oa c h. In a f ir s t s tep ,

F ig ure 1 : Sens o r a nd ex a m pl e o f a ct iv it ies ac ti v it y s eg m en ts are s eg m en ted , di s c ard in g oth er pa rts of the c on ti nu ou s ac c el era ti on s ign a ls . T he s ec on d, ac tua l rec og ni ti on s tep c om pa res an d c om bi ne s two ap p roa c he s to c las s if y s eg m en ted ac ti v it ies : d ir e c t pa tte rn m atc hi ng y ie ld in g s im ilarit ies thro ug h D y n am ic T im e war pi ng (DT W ) and s tat is ti c a l fea tures . S im ilarit ies an d fea tures are us ed as i n pu ts i n a Li n ea r Di s c ri m ina nt c las s if ier in a lea v e -on e - s ub jec t o ut pa rad igm tr ai n -t es t s ett ing . 3. RE S UL T S A N D DI S CU S S IO N Com bi na ti on of the DT W a nd s tat is ti c al f ea tures y ie lds s ign if ic a ntl y s u pe ri or p erf or m an c e c o m pa red to ea c h of th e m s ep aratel y , wi th an av era ge ac c urac y u p t o 93 .6% . T he s e po s iti v e res ul ts pa v e the w a y f or the ne x t s tag e, the au tom ati c an d inte rpret ab le as s es s me nt of f un c ti on al c ap ac it y , the s u bj ec t of c urr en tl y on go ing r es ea rc h. Ref er en ce s [1] A tta l, F. et a l. P h y s ic al Hu m an A c ti v it y R ec og n iti on Us ing W ea rab le S en s ors .S en s ors 15 , 1 2 ( 2 01 5), 3 13 14 – 31 33 8. [2] Cal in, A et al . A ne w ap pro ac h t o de fi ni ng fun c ti on a l a bi lit y i n an k y los ing s po nd y liti s : the d ev el op m en t of th e b at h a nk y los ing s po nd y liti s f un c ti on al i nd ex . J Rhe um ato l 21 , 1 2 (19 94 ), 22 8 1 -22 8 5