DIFF DATA INTERFACE FILE FORMAT (DIFF) USER`S MANUAL
Contents
1. 04 2200 04 2211 04 2212 04 2221 04 2222 04 2300 Quadriplegia Partial quadriplegia C1 C4 Partial quadriplegia C5 C8 Full quadriplegia C1 C4 Full quadriplegia C5 C8 Miscellaneous spinal dysfunctions from external damage 05 0000 Amputation 05 1000 05 2000 05 3000 05 4000 05 5000 05 6000 05 7000 05 9000 Unilateral amputation above the elbow AE Unilateral amputation below the elbow BE Unilateral amputation above the knee AK Unilateral amputation below the knee BK Bilateral amputation both above the knee AK AK Bilateral amputation one above one below AK BK Bilateral amputation both below the knee BK BK Miscellaneous combination 06 0000 Arthritis 06 1000 06 2000 06 3000 Rheumatism Osteoarthritis Miscellaneous 07 0000 Pain 07 1000 07 2000 07 3000 07 9000 Neck pain Back pain Pain in extremities Miscellaneous pain 08 0000 Orthopedic 08 1000 08 2000 08 3000 08 4000 08 5000 08 6000 After fracture of the hip joint After fracture of the femur shaft After pelvic fracture Multiple fracture of major joint After total hip replacement After total knee replacement 20 08 9000 Miscellaneous orthopedic 09 0000 Heart disease 10 0000 Lung ailments 10 1000 Chronic obstructive lung disease 10 9000 Miscellaneous lung disorder 11 0000 Burns 12 0000 Congenital defects 12 1000 Double spine 12 9000 Miscellaneous congenital defects 13 0000 Miscellaneous dysfunction2. for example FRF for floor reaction force or A1R for joint angle etc These are named data type code The second item for each sampling data will be the time in seconds and for the third up to a maximum ofthe 32nd item gait data will be set in fixed orders These essential data items are specially called numerical data items Ifa numerical data item is invalid 9999 9 will be set as a invalid data item Each sampling data 11 contains data items which were captured at the same time When we say one sampling data here it means all contents from the first character after a carriage return CR plus linefeed LF up tothe next CR LF pair One sampling data may contain up to 32 items delimited by commas In cases wherea sampling data does not contain data entries for all 32 items then 9999 9 is to be set after the last item as the terminator of the sampling data A sampling data can be terminated by 9999 9 if all items after a given item are invalid The sampling data are to be set in time sequence starting with the earliest Example FRF 0 00 1 2 0 1 0 2 9999 9 CR LF FRF 0 01 0 2 0 1 40 8 9999 9 CR LF FRE 0 02 12 7 23 2 69 4 9999 9 CR LF FRE 0 03 10 2 49 4 113 1 9999 9 CR LF FRE 0 04 13 4 62 1 9999 9 9999 9 CR LF etc etc etc etc FRF 0 62 2 3 0 1 1 2 9999 9 CR LF Set 9999 9 at the last of each sampling data Floor reaction force vertical component in newtons Floor rea
3. the coordinate system for the left limb is also to be used for the trunk 34
4. The origin of fore and aft and right and left axes must coincide with the origin of the point of force application in FRF if force plate data was measured simultaneously Incase of the measurement without force plate the origin depends on_ user s preference 26 One Sampling data of Space Displacement Data for Left Limb Contents o oNu oan kh wry He wn ne nN NNN NNN NHB HB eee ep ee mMON OAK ANHNH DAH AAR A BRwWNYH O Data type G1L Time Top of head L side Acromion Hip joint Knee joint k Ankle joint Metatarsus LR right FWD forward VERT upward LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT Unit seconds 27 Hip joint geometric center of the acetabulum Knee joint fore and aft and mediolateral center of the femur at the height of maximum fore and aft diameter of distal end of the femur in standing position Ankle joint center pointofthe line connected medial and lateral malleolus Metatarsus center point of the line connected medial 1 metatarsal and lateral 5 metatarsal Toe most forward part of the foot The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end after the last item Note Even if the forward direction of walking changes
5. angles joint moment location of center of gravity and EMG etc When you code a conversion program from your format to DIFF you should remember that you don t have to convert all DIFF data You only have to convert data which you want to and you can convert For example if you don t have joint moment calculation program you don t have to convert joint moment data If you have a goniometer system you may convert only body segmental angles When you have 3D camera system you can calculate XYZ coordinate of the landmarks and body segmental angles but you don t have to convert both data Because body segmental angles are easily calculated from the landmark data on DIFF data file So it is all up to you whether you convert both landmark data and angle data or convert only landmark data DIFF was originally proposed as the common structure of the computer datafile So one should strictly be followed to the described structure to convert and use DIFF file DIFF structure will not be changed in a near future However we have another concept for the contents of the DIFF data file We think that the contents or definitions of the items should be the subject of discussion while we are using DIFF for ever For example there is no adequate and sufficient definition for the body segmental angles so far Whenever better method comes up DIFF definition should be changed And best definition will depend on his own purpose of the measurement In additi
6. causing maladies The next 2 bytes after the disability code are the disability side code 01 Right side affected 02 Left side affected 03 Both sides affected Note 3 The subject s age is indicated by the quotient of the number of days difference between the year month and day of measurement and the year month and day of the subject s date of birth divided by 365 25 rounded to three decimal places When it is not necessary to show this so strictly the age can be converted to an integer forthe actual number of years for example 36 0 for someone 36 years old Note 4 For item 14 and on first write the filename extension of the data file and data type code such as DA C FRF and then after the delimiting comma write the number of data per channel for that data notin binary but in ASCII For example for 21 data ata frequency of 50 Hz from 0 00 second to 4 00 seconds this number would be 201 The order of the data type is the user s option Also data types not measured does not need to be written Example of items from 14 on re DA_ FRF 201 DA_ G1R 201 FRF FRF 201 Data file with the extension DA FRF and G1R would have 201 data per channel Also this means that data file with the extension FRF FRF would have 201 data as well Sample of Information File Facility name Data ID Patient ID Version No Tokyo 90123A X32819A Ver 1992 06 Comment A Date of Patient s Patient s measurement w
7. must consist of eight characters plus the filename extension INF IDIDIDO1 INF Sequential No to indicate the number of trial Data ID Example 90123A01 INF D9412305 INF GEORGEO1 FRF TEST_01 FGE 15 Data file The filename will be the same as that of the corresponding information file but with a different filename extension IDIDIDO1 DA a case for compound type file IDIDIDO1 FRF a case for single type file if only FRF is included Sequential No to indicate the number of trial Data ID same as with an information file For the filename extension DA is used fora compound type fileasarule Incase of single type file the extension name as same as the data type codeis used asarule However any other characters can be used for the extension if necessary Example 90123A01 DA D9412305 DA GEORGEO1 FRF TEST_01 FGE 16 CHAPTER 3 CONTENTS OF AN INFORMATION FILE 10 11 12 13 Contents Facility name enclosed in double quote marks within 8 characters Ex TOKYO Data ID enclosed in double quote marks within 8 characters Ex 90123A see note 1 Patient ID enclosedin double quote marks within 50 single width characters equivalent to 25 kanji characters Version number of format Ex Ver 1992 06 as with this version Comment A enclosed in double quote marks within 254 single width characters equivalent to 127 kanji characters Overall comment common to multiple trials of walking the first 7 bytes are
8. the sampling rates for floor reaction force and joint angle are different 7 As long as the sampling data are in time sequence it does not matter if floor reaction force data starts and or ends in the middle of time sequence It does not matter if time does not start from 0 0 sec 13 8 There is no specific limit on the number of characters for each item ofthe sampling data as long asthe entire sampling data does not exceed 240 bytes Numeric values must have decimal points and exponential format is not to be used 9 Spaces may be added or not added according to the user s preference between the delimiting comma and the next item 10 New data types can be added at any time as necessary This limitation comes from the limitation of some commercial spread sheet programs when they read a text file into their work area Some Points of Caution when Creating Conversion Programs 1 All data contained should be converted to a physical value 2 The coordinate system is defined as subject oriented coordinate rather than space oriented coordinate which is fixed to the walking path This means for example ifthe subject goes and returns the path the fore and aft and _ right and left coordinates will be reversed 3 The coordinate system for space displacement data must be the same for all measurements devices For example the coordinate system for point of application of floor reaction force and that for spac
9. to be the disability code and the next 2 are the disability side code see note 2 Date of measurement Western date yr mo da Ex 19910514 Subject s weight in kg Ex 62 3 Subject s height in cm Ex 178 2 Subject s date of birth Western date yr mo da Ex 19620303 Subject s age in years old Ex 29 195 see note 3 Subject s gender M for male F for female Healthy or handicapped ABLE for healthy HANDI for handicapped Comment B enclosed in double quote marks within 254 single width characters equivalent to 127 kanji characters Comment related to the current trial of walking 17 for example rapid walking 14 Ex DA_ FRF see note 4 _ means one space character 15 Ex 201 number of data per channel fora FRF type data in a file with the filename extension DA 16 Ex DA GIR 17 Ex 201 number of data per channel for a G1R type data in a file with the filename extension DA 18 Ex DA GIL from 14 on repeated as necessary The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end after the last item Kanji characters may be used when entering items 5 and 13 above Kanji characters may also be used when entering items 3 if necessary Note 1 The data ID is the filename excluding the rightmost two characters before the period and filename extension For example if th
10. to exchange their gait data which are measured with different systems It is more convenient to have one common format than to have many conversion programs depend on the other party Because when we have one common format we must have only two conversion programs One of which is a conversion program from one s format to the common format and another is a conversion program from the common format to one s format In this way the common format will be served as an intermediate format between each format So we named the common format Data Interface File Format DIFF We don t intend to have any standard format which restricts a development of a new system Each system can have any format for his own As for DIFF there are two purposes for the clinical gait analysis The first purpose is to construct a Data Base of the clinical gait analysis We hope the vendors and researchers to develop at least the conversion program from their format to DIFF And we also hope that they could send their gait data in DIFF to the Gait Library Center to accumulate many gait data If many researchers could send us their data in DIFF we can build a Gait Data Bank including a variety of age sex height weight way of walking and abnormalities We will distribute the data to clinicians who need the data for their references This process will enhance the possibility of the clinical usage of the gait measurement system very much Theinformation file of DIFF whi
11. 1 Data type S1B 2 Time seconds 3 Head Fore and aft leaning angle back degrees 4 LR bending angle left A Bu LR rotation angle left 6 Abdomen same as above 3 7 i goo i 9 Pelvis 7 i 10L n 11 12 9999 9 The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end of the line after the last item The spatial angle of a body segment is the relative angle formed between the coordinate system for the walking path and the coordinate system for the body segment The coordinate system for the walking path is fixed coordinate system for the waling path and the coordinate systems for the body segment are fixed coordinate systems for each respective body segment The spatial angle is defined for the right limb coordinate a the angle from the vertical axis as viewed from the right hand plane in sagittal plane b the angle from the horizontal axis as viewed from the rear in transverse plane c the angle from the forward axis as viewed from above with counterclockwise as positive 33 For the left limbs a the angle from the vertical axis as viewed from the left hand plane in sagittal plane b the angle from the horizontal axis as viewed from the rear in transverse plane c the angle from the forward axis as viewed from above with clockwise as positive For convenience
12. DIFF DATA INTERFACE FILE FORMAT DIFF USER S MANUAL English Version Compact version Ver 1992 06 Clinical Gait Analysis Forum of Japan Publication of this document was partly supported by Marubeni Kikai Boeki Co Ltd Japan and B T S Italy English version is available only in compact version To COPY this document is ALLOWED When you have any questions please contact to Yoshihiro Ehara Ph D Rehabilitation Engineering Department Kanagawa Rehabilitation Center Nanasawa 516 Atsugi city KANAGAWA 243 01 JAPAN FAX 81 462 49 2290 CONTENTS PREFACE CHAPTER 1 GENERAL DESCRIPTION Introduction Form of Files Overall Configuration of Files Information File Data File Some Points of Caution when Creating Conversion Programs CHAPTER2 ASSIGNING A FILENAME Information File Data File CHAPTER 3 CONTENTS OF AN INFORMATION FILE CHAPTER 4 CONTENTS OF A DATA FILE One Sampling Data of Floor Reaction Force Data One Sampling Data of Space Displacement Data for Right Limb One Sampling Data of Space Displacement Data for Left Limb One Sampling Data of Space Displacement Data 2 for Right Limb One Sampling Data of Space Displacement Data 2 for Left Limb Appendixes are not included in the compact version 10 11 15 PREFACE Data Interface File Format DIFF is a computer file format to store time series data for Gait Analysis This is proposed as a common data format to use when researchers want
13. at is actuary useful to enhance the quality of life of the handicapped After that we will be able to discuss whether we should have only one common data format in the world Any wayto have a conversion program between DIFF and CAMARC datafile might be useful for the discussion And there are no technical difficulties to do that so it will be done in the near future 1994 4 7 CHAPTER 1 GENERAL DESCRIPTION Introduction This chapter gives the general structure of the common format for gait analysis Avariety of methods have been considered for how to use the standard format but we propose the method which does not assign any limitation of each facility and each maker s format When the necessity arises to exchange data with another facility etc two companies would use a common format proposed here as an intermediate Namely data being sent can be converted from the sender s format to the common format whereupon the receiver can convert from the common format to his own format herein referred to as back converting Therefore the common format is called as Data Interface File Format DIFF This format is applied to time sequential waveform data such as floor reaction force joint angle etc but is not applied to statistical data such as average walking speed stride length and peak value of floor reaction force etc Form of Files 1 Stored as text format sequential files 2 Alphanumerics are written in ASCII codes how
14. ch contains the information of subjects etc willbe served as the management information to retrieve gait data from the data base We already started the service of the Gait Library Center in 1992 and over 100 gait data have been accumulated so far The second purpose of DIFF is to hold computer programs in common We hope the researchers to develop computer programs to analyze gait data in DIFF and to register the programs to the Gait Library Center to serve it as common properties Over 20 application programs have been already registered including a stick picture animation program an artifact modification program a joint momentcalculation program and so on We distribute these common properties to the clinician who want to analyze DIFF gait data This process will also help the clinician to improve the quality of life of the patients When the library programs become sufficient one can easily analyze DIFF gait data without having the conversion program from DIFF to one s format Of course a person who has the conversion program from DIFF to his own format can analyze DIFF gait data with his own application programs DIFF is written in ASCII format so it is independent from its operating system It can be used in MS DOS WINDOWS UNIX and Macintosh etc Even when new OS appears DIFF will be able to be used init DIFF isa format very easy to be understood DIFF is a format very easy to be used It s information file can be input direc
15. ction force fore and aft component in newtons Floor reaction force right left components in newtons Time in seconds Data type code to indicate that these are data for floor reaction force CR LF means JIS carriage return character and a JIS linefeed character 9999 9 is an invalid data code 12 4 When there are different typesof data such as floor reaction force and joint angle each willbe puton a separate sampling data even ifthe time is the same in which case the order does not matter However the time must be sequential overall Example FREF 0 00 CR LF A1R 0 00 0 CR LF FRE 0 01 0 CR LF A1IR 0 01 aeee CR LF FRE 0 02 0 00 CR LF AIR 0 02 eee CR LF 5 The file in the above example is a compound type with FRF and A1R data within the same file Ina compound type file all types of datasuchas FRF and A1R and any other types shown in this manual can be written within one file On the other hand a file contained only one type of data for example FRE data ina FRF file or A1R data in a A1R file is called single type file Either single type or compound type may be used at the user s option as long as the DIFF rules are satisfied If the user wishes to work with the single type files several data files and an information file can be created for one trial of walking 6 As long as the sampling data are in time sequence it does not matter if
16. during measurement the coordinate system forthe time of start of measurement does not change Note Origin for the vertical axis is the surface of the floor The origin of fore and aft and right and left axes must coincide with the origin of the point of force application in FRF if force plate data was measured simultaneously Incase of the measurement without force plate the origin depends on_ user s preference 28 One Sampling data of Space Displacement Data 2 for Right Limb No Contents Unit 1 Data type G2R 2 Time seconds 3 Top of head LR right m 4 FWD forward ii 5 t VERT upward a 6 Reside Tragus LR n 7 y FWD 2 8 i VERT 9 m Acromion LR 5 10 7 n FWD n 11 VERT 12 Shoulder joint LR 13 h FWD y 14 7 n VERT j 15 Elbow joint LR 16 7 k FWD 7 17 x VERT Y 18 1 Wrist joint LR 19 7 FWD 20 7 k VERT 4 21 Fingertips LR J 22 FWD 23 n N VERT P 24 9999 9 The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end after the last item Note Even ifthe forward direction of walking changes during measurement the coordinate system for the time of start of 29 measurement does not change Note Origin for the vertical axis is the surface of the floor The origin of fore and aft and right and left axes must coincide with the origin of the po
17. e displacement data must be the same 4 The origin of the coordinates for space displacement origin for the right and left and the fore and aft axes must coincide with the origin of point of application of floor reaction force of the force plate The surface of the floor is the origin for the vertical axis 14 5 The direction of axis of the coordinates for space displacement for right and left right shall be positive and for fore and aft forward positive and for vertical upward positive 6 Definitions of points of articulations are given in chapter4 and details for how to attach markers to the joint and the way to estimate the point of each articulation from markers is given in Appendix A1 7 Definitions of spatical angle of body segments and relative angles are given in chapter4 and details for how to calculate angles from coordinate data are given in Appendix A2 8 The precision registration formats for floor reaction force data as well as for 3 dimensional coordinate data are given in Appendix A3 Appendixes are not included in this compact version CHAPTER 2 ASSIGNING A FILENAME Information file As to how a filename is assigned the first six characters will be the data ID the next two characters will be numerics assigned in sequence starting with 01 then incremented to 02 etc to indicate the number of the trial of the current round These numerics are named the sequence No Therefore the filename
18. e filename not including the extension is 90123A02 then 90123A would be the data ID Note 2 The first 7 charactersof comment A must be the Disability Code The disability Code represents the classification of the dysfunction according to the Functional Independence Measure FIM For subjects with multiple disability the disability code whichis the main cause of walking dysfunction should be written 18 Disability Code 01 000 Cerebral apoplexy 01 1000 Left side paralyzed right brain disability 01 2000 Right side paralyzed left brain disability 01 3000 Both sides paralyzed 01 4000 No paralysis 01 9000 Miscellaneous cerebral apoplexy 02 000 Brain dysfunction 02 1000 Internal brain damage 02 2000 Traumatic brain damage 02 2100 Disconnection 02 2200 Nondisconnection 02 9000 Miscellaneous brain dysfunction 03 0000 Neural disorders 03 1000 Multiple sclerosis 03 2000 Parkinson s disease 03 3000 Multiple neuritis 03 4000 Guillain Barre syndrome 03 9000 Miscellaneous neural disorders 04 0000 Spinal dysfunctions 04 1000 Internal damage 04 1100 Paraplegia 04 1110 Partial paraplegia 04 1120 Full paraplegia 04 1200 Quadriplegia 04 1211 Partial quadriplegia C1 C4 04 1212 Partial quadriplegia C5 C8 04 1221 Full quadriplegia C1 C4 04 1222 Full quadriplegia C5 C8 04 1300 Miscellaneous spinal dysfunctions from internal damage 04 2000 Traumatic damage 04 2100 Paraplegia 04 2110 Partial paraplegia 04 2120 Full paraplegia 19
19. e the filename must consist of eight characters plus the filename extension INF Example TEST__01 INF 3 In this case the data ID isa name assigned to whole data which contains several trials of a given subject 10 4 The contents are shown on a separate sheet Data File 1 For one trial of walking at least one data file will be created In some cases more than one data file will be created 2 The filename will be the same as that of the corresponding information file but with a different filename extension This means that the first six characters will be the data ID the next two characters will be numerics assigned in sequence starting with 01 then incremented to 02 etc to indicate the number of the trial of the current round of walking The default file name extension for the data file willbe DA However as discussed later if the datafile contains only single type data for example FRF data then sucha file may be given the filename extension FRF Ifthe data filecontains some combinations of data arbitrary filename extension forexample FGE will be possible Example D9012301 DA D9012301 FRF TEST__01 FGE 3 Ina data file data for one trial of walking are written more than one line Each line is named one sampling data and each element contained in the sampling data is named data item Characters indicating the type of data enclosed in double quote marks are to be set as the first item of each sampling data
20. eight in kg height in cm 05 30001 19910514 64 5 178 20 Patient s yr mo da patient s Patient s of birth age gender 19620308 29 195 M Healthy or Comment B Type No of data handicapped HANDI Readily DA_ FRF 201 Type No of data Type No of data DA_ G1R 201 DA_ G11 201 CR LF _ means one space character 22 CHAPTER 4 CONTENTS OF A DATA FILE One Sampling Data of Floor Reaction Force Data No Contents Unit 1 Data type FRE 2 Time seconds 3 FRFLR_ component R foot right newtons N 4 FWD component forward y 5 VERT component reaction force N 6 LR component L foot right 7 7 FWD component forward 4 8 VERT component reaction force 9 LR component LR cmb right A 10 FWD component forward 11 VERT component reaction force i 12 FRF point of application LR R foot right m 13 8 FWD forward 14 LR Lfoot right i 15 FWD forward 16 LR LR cmb right r lga al FWD forward 18 Torque around vert axis for point of appl R foot opposing torque counterclockwise as viewed form above Nm 19 L foot i 20 LR cmb 21 9999 9 see note The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end after the last item 23 Note If there is no further information
21. ever Shift JIS can be used for comments in information files discussed later 3 Information files will be created separately from data files Overall Configuration of Files 1 The gait data continuously taken in from the time when the START button of the data collection device is pressed until when the STOP button is pressed is called one round of gait data 2 For each round of walking an information file in which the information of the subjectand the information showing the conditions of the way of walking are written will be created The contents will be explained in the next paragraph 3 For each round of walking at least one data file in which that round of gait data are written will be created With the later discussed single type data file there will be cases where more than one data file would becreated for one round of walking 4 As mentioned above there will be an information file and at least one data file for each round of walking For n rounds of walking there will be n information files and at least n data files Information File 1 One information file is created for one round of walking 2 As to how a filename is assigned the first six characters will be the data ID the next two characters will be numerics assigned in sequence starting with 01 then incremented to 02 etc to indicate the number of the trial of the current round These numerics are named the sequential No Therefor
22. int of force application in FRF if force plate data was measured simultaneously Incase of the measurement without force plate the origin depends on user s preference 30 One Sampling data of Space Displacement Data 2 for Left Limb No Contents Unit 1 Data type G2L 2 Time seconds 3 Top of head LR right m 4 FWD forward i 5 u VERT upward i 6 Lside Tragus LR 7 7 k FWD k 8 i VERT 9 m Acromion LR 5 10 7 n FWD i 11 VERT 12 Shoulder joint LR 13 h FWD y 14 7 n VERT j 15 Elbow joint LR 16 7 k FWD 7 17 x VERT Y 18 1 Wrist joint LR 19 7 FWD 20 7 k VERT 4 21 Fingertips LR J 22 FWD 23 n N VERT P 24 9999 9 The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end after the last item Note Even ifthe forward direction of walking changes during measurement the coordinate system for the time of start of 31 measurement does not change Note Origin for the vertical axis is the surface of the floor The origin of fore and aft and right and left axes must coincide with the origin of the point of force application in FRF if force plate data was measured simultaneously Incase of the measurement without force plate the origin depends on user s preference 32 One Sampling Data of Spatial Angle for Body Segment No Contents Unit
23. on to that he may prefer simple definition than complicated one So we don t want to restrict any items to only one unique definition It might disturb the development of the new method for gait analysis As for the accuracy of DIFF data our basic concept is as follows One of the purpose to propose DIFF is to build a Data Base We know that if the accuracy is not sufficient we will not be able to use the Data Base However we also know that if the requirement ofthe data accuracy isso high nobody will offer his data The main reason to build the Data Base is to realize the value of it s existence When many people find its usefulness they will make every efforts to offer accurate data So we don t want to set any standard concerning the accuracy Instead we request the person who offer the data to show the check sheet of the accuracy described in Appendix So the user of the Data Base could refer the check sheet to find whether the accuracy of the data is good enough for his purpose As the last comment we will tell you about worldwide common format We know that CAMARC projectis having their standard format in EC We don t think that DIFF and CAMARC data format oppose each other Instead we think both can come into coexistence We may learn from each other of their distinctive features We will need some trial period for both to check and solve our own problems And also we need some trial period to realize that having a common form
24. ta XYZ coordinates of the specific points on the body in DIFF data file are not the locations of the landmarks For example XYZ coordinate of the hip joint may be estimated from the several landmarks around the hip joint So you don t have to know much about the arrangement of landmarks We will give you another example about the contents of DIFF data When we say XYZ coordinates of the hip joint it is a kind of final target location tobe calculated However we don t know the perfect method to measure the location of the hip joint by now So wehavetoestimate the location by some means One may use simple way and the other may use complicated way As an extreme case the location of the landmark fixed on the skin around the greater trochanter can be the first approximation of the hip joint We don t want to enforce you to use one of the specific method It is up to you to select the method because it depends on your research purpose So it is requested to describe your method somewhere In this way you are requested strictly to follow the data structure of DIFF but you are not requested strictly follow the definition of each data item We have to discuss to find the best definition continuously DIFF might be very useful for the discussion based on the actual gait data This document describes basicconceptof DIFF and data arrangement such as XYZ coordinate ofthe specific points on human body floor reaction forces body segmental
25. tly into any commercial data base systems to serve as a management information such as name of the subject date of measurement and name of the operator etc Its data file can be input directly into any commercial spread sheet programs Information file and data file can be edited and modified with any editors and or word processors In DIFF data file any kind of gait data can be stored There are no limitations for the number of data Any data of any sampling rates can be stored in DIFF data file Even when the sampling duration and the sampling rate are different each other for each data no problems will be happened All data may not be started and ended at the same time In this way DIFF is highly flexible format to store the time series data for gait analysis motion analysis and any kinds of analysis The contents of DIFF data file is device independent Data are not expressed in output voltages etc Instead data are expressed in the physical values such as Newtons degrees meters etc No further calculations will be required to use DIFF data The contents of DIFF data file is Lab independent For example it does not depend on the force plates arrangements nor it does not depend on the 3D camera arrangement It does not depend on the direction of the walking The positive direction of Y coordinate is always the direction of the subject walking So you don t have to know anything about the Lab setups DIFF data is human body oriented da
26. tobe entered beyond these items enter 9999 9 at 21st item and then a hard carriage return CR LF 24 One Sampling data of Space Displacement Data for Right Limb Contents o oou oan kh wry eH wn ne nN NNN NNN NHB HB eee ep ee mMON OAK ANHNH DAH AAR A BRwWNYH O Data type GIR Time Top of head R side Acromion Hip joint Knee joint k Ankle joint Metatarsus LR right FWD forward VERT upward LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT LR FWD VERT Unit seconds 25 Hip joint geometric center of the acetabulum Knee joint fore and aft and mediolateral center of the femur at the height of maximum fore and aft diameter of distal end of the femur in standing position Ankle joint center pointofthe line connected medial and lateral malleolus Metatarsus center point of the line connected medial 1 metatarsal and lateral 5 metatarsal Toe most forward part of the foot The above contents are to be entered delimited by commas A CR LF pair hard carriage return is not to be inserted anywhere within these contents but is to be placed only at the end after the last item Note Even if the forward direction of walking changes during measurement the coordinate system forthe time of start of measurement does not change Note Origin for the vertical axis is the surface of the floor
Download Pdf Manuals
Related Search