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2011 www.design-engineering.ee CURA
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2011www.design-engineering.ee
CURA
2
Janno Nõu - product designer, Estonia
Alan Guillemot - Engineer, exchange student, France
Larissa Frosch - product manager, Estonia
Madheswaran Chidambaram - structural engineer, India
3
Introduction 4
Subject research 4
Innovation context 10
Global solution 11Monitoring Devices Pre-concepts
Usability 14BraceletTabletStoryboard Everyday life Working-out
Technical working 24
Patches 25Motion sensorWireless connectionAutonomy calculation
Bracelet 26Wireless connectionMicrocontrollerMemoryVibration alarmVisual alarmSound alarmActivity display
Tablet 28Wireless connection MemoryMicrocontrollerLCD displaySpeaker
Service 29
Further developments 31
Conclusion 31
References 31
Appendixes 33
Contents
4
Introduction
Subject Research
We started the project with a superficial overall re-search which lasted one day and after what we nar-rowed our project scope down. We chose the theme of motivation which had to be narrowed down further as it was still way too wide. We introduced three sub-themes: seniors, equilibrium and interaction which were narrow enough to get usable results out of the research. Output of the research was a giga-scale map (more than 300 en-tities) that brought out the problem and illustrated the overall situation quite well (the map itself can be seen here: dl.dropbox.com/u/20271965/Map.pdf ).
We discovered that quite many problems among older people are accident related. Accidents are the only domain in health care that will increase as population is getting healthier and with aging population accident related injuries and results are demanding more and more money.
The population percentage that is over 65 will skyrocket in the beginning of the 2nd decade of 21st century be-cause of the post WW2 baby boom. In 2030, the propor-tion of those over 65 will be 33% in Australia, or 50% in Germany. A really important factor is also the amount of healthy years to live for people 65 years old which shows that poorer countries who don’t have enough money to spend on personal healthcare have problems with many ill people who haven’t received full deten-tion, this in turn will demand even more money. After retiring your physical activity decreases, increasing the chance of accident with serious consequenses.
This report is a conclusion of our teamwork on concep-tual design studies.The aim of this assignment is to develop a concept for personal training device. All though we started the de-sign process with the classical gym equipment we real-ised only after several backfirings that our project had a different angle for the theme. It took an independent workshop that was comfortably joined with the project to really get a firm foundation to get going.
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Population
Population is ageing, that means there are more and more people who won’t work.
After retiring your physical activity decreases.
Population percentage who is over 65 will skyrocket in
the beginning of the 2nd
decade of 21st century because of the post WW2 baby boom.
BREAKDOWN FOR WOMENLife expectancy/healthy years after age 50UK: 82.7/20.8France: 85.4/19.7Spain: 85.0/18.6Finland: 84.1/13.9Sweden: 84.0/20.3Austria: 83.7/15.7Germany: 83.0/13.5Denmark: 81.9/24.1Estonia: 80.5/10.4Latvia: 79.3/12.7
BREAKDOWN FOR MENLife expectancy/healthy years after age 50UK: 79.5/19.7Sweden: 80.3/20.2France: 79.6/18.0Spain: 79.5/19.2Austria: 79.1/14.5Germany: 79.0/13.6Finland: 78.5/12.9Denmark: 78.3/23.6Estonia: 72.4/9.0Latvia: 71.3/11.0
In 2030, the proportion of those over 65 will be 33% in Australia, or 50% in Germany.
It has been stated in many papers that bone fracture among older people is a serious concern as it will lead to a decrease in life quality in about half of the cases. Two thirds from among the people who will even recover won’t get back the same movement level as they had before the accident. The hip fracture is usually stated to be one of the most serious that will lead to immobil-ity, decrease in life quality, fear and quite often to next fracture or another illness. Amazingly there hasn't been any serious research to find out how many deaths that are caused by other factors can be traced back to hip fracture. Swedish health care report thinks it to be up to three times as much as there are deaths caused directly by hip fracture. Accident and bone fracture that will decrease your moving capacity can be described as a self feeding circle. Quite often people who have had bone fracture in the older age and even completely healthy people who are in the older age will develop fear of falling. This in turn will lead to moving less that will decrease the equilib-rium and muscle fitness and this increases the likelihood of falling and fracturing a bone. Once fallen the fear of fall will increase and the circle starts again.
WESTERN EUROPE IN DETAIL
30–5020–29.9Not Illustrated
10–19.90–9.9
Old-Age Dependency Ratio2020 forecast %
6
Major health problems among seniors
Cardiovascular – hypertension, heart
attack, rupture of blood vessels etc. are common
disorders in old age.
about half of the population over
65
Musculoskeletal – osteoporosis, spasm, drooping
shoulder are invariably found in aged people.
Endocrinological – diabetes is major disease.
Opthalmic – Eye problem is very common in old people.
Hearing – loss of hearing and hard- hearing are the major hearing problems of old age.
Osteoporosis
Cancer – the danger of cancer is multiplied with the advancement of age.
Psychological Problems and Emotional problems
Accident injuries
While population is getting healthier, the
amount of accident injuries is increasing
Musculoskeletal pain
Sight impairments
Diabeties
Avoid falling down
• Regular physical activity• Equilibrium exercises (weight
shift, knee flexion, toe raise, etc.)• Good shoes• Grab bars / handrails• Avoid domicile dangers (carpets
tacked down, stable chairs, etc.)• Tai Chi
Reduce the fall effect
• Healthy diet (stronger bones)• Hip protector
Rehabilitation
• Immobilisation (Cast, lay in bed, etc)
• Surgery• Training (continued after reha-
bilitation) *Physiotherapist *Rehabilitation centre *In-home assisted care• Healthy diet
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Here are four cases that describe the situation of hip fracture:
Full health—Anne She lives in her own home and cares for herself. Anne is active in her local commu-nity and is out and about with friends quite a bit. She swims regularly and enjoys visiting her children each weekend. Anne walks without any aids and can manage her 12 steps at home without any problems. She enjoys shopping and cooking for herself. Anne does not need any help with the housework and derives pleasure and relaxation from gardening.
The circle that describes falling is linked with another one that describes social isolation. People who are recov-ering from fracture are in bigger risk to be left in social isolation. Right now there are two solutions for people recovering to help them get back their confidence and mobility. One of them includes staying at rehabilita-tion center where professionals have the know-how and equipment to help, but staying outside home will de-crease motivation and about half of the people wont go back home. Second of them lets people to stay at home and is a device (protective padding) that you wear on your hip, it doesn’t do much more than give you reassur-ance that when you fall then there is bigger possibility that you won’t fracture anything. This will obviously work only when you wear it. Rehabilitation while living at home will give older people much more motivation as they can see the possibility of getting along by them-selves. It has been noted that people staying at home have still problems with motivation - for some reason they won’t do enough exercises. They have the goal in sight but they don’t exercise enough, when they do though they have better results than people who stay at a rehabilitation centre. When people fail to recover they face really serious consequences. A staggering eighty per cent of women who have survived a hip fracture would rather be dead than experience the loss of inde-pendence and quality of life that results from a bad hip fracture and subsequent admission to a nursing home.
Fear of falling—Mary She lives alone in her own home and cares for herself. Mary is involved in community fundraising and enjoys playing bridge. Mary recently had a fall. She did not break any bones but was badly cut and bruised. She is scared of falling. Mary continues to walk without aids. She still looks after herself and does her own housework. Mary has been a bit depressed since her fall. She has returned to her bridge group but is anxious when she is outside the home because she is scared of falling again.
Good hip fracture—Jean She lives in her own home and cares for herself. Before her fall Jean was out and about quite a bit with her church group. She swam on a regular basis and occasionally looked after her grand-children. Jean broke her hip when she fell. She is finding it difficult to do everything at home now that she walks with a stick. She needs help in shopping as she no longer drives or feels confident to shop alone. She can prepare
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(FoF)
Lack of
+ afraid to go out
- contact with store keepers
- di�culties to meet people
-
+ no more relationship with the partner
- decrease the walk and drive avility
- di�cult to go to activity places
+ less money
- less involved in the society
- no more buisness asociates
+ emotional support, Hobbies, solidarity
+ practical support
+ emotional support
- don’t meet people
- poor respect
- poor respect
+ group activities are possible
stay at home
no sucsess
immobility
impact
Back problems
lack of training
bad experience
equilibrium is controlled by deep muscles
only simple meals and is missing being able to bake for her friends. Jean can no longer manage the housework by herself. She misses her church activities but finds it too painful and tiring to be out for long periods. Jean experiences feelings of frustration and anger. Jean gets tearful thinking about all the things she can’t do.
Bad hip fracture—Elizabeth Until her recent fall, she lived in her own home and managed to care for herself. She was active in her local community.Elizabeth broke her hip when she fell. She is now unable to live alone as she requires a great deal of help to do most things. Elizabeth now lives in a nursing home near to her family but away from her friends. She is limited in where she can walk because of the frame and is un-able to walk for long distances. She is unable to shower or dress without help from the nurse. She is unable to pursue her gardening or community work. Her leg
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(FoF)
Lack of
+ afraid to go out
- contact with store keepers
- di�culties to meet people
-
+ no more relationship with the partner
- decrease the walk and drive avility
- di�cult to go to activity places
+ less money
- less involved in the society
- no more buisness asociates
+ emotional support, Hobbies, solidarity
+ practical support
+ emotional support
- don’t meet people
- poor respect
- poor respect
+ group activities are possible
stay at home
no sucsess
immobility
impact
Back problems
lack of training
bad experience
equilibrium is controlled by deep muscles
aches sometimes at night. She has become anxious and is easily upset.
We decided to concentrate on the circle that will de-velop after the fall and put our efforts towards easing the problem and helping along with rehabilitation after hip fracture. We went to Viimsi hospital to speak with physiotherapists working there. When mapping the situation in real life, we learned that the problem is not in the hospital but at home. Rehabilitation hospitals are quite well equipped. The equipment is simple, elegant, professional and easy to use but with the help of a thera-pist. Furthermore, it turns out that most of the older people, at least in Estonia, don’t have enough money to buy necessary equipment for themselves, which means going to therapy regularly. But most people will start going to therapy far too late.
10
In case of a serious joint fracture, the recovery period is divided in 4 parts.For instance after a hip fracture surgery with prosthe-sis in Estonia:• The patient will stay maximum 14 days in the hospi-
tal.• A medical visit is planned 2,5 month after surgery.
If the joint can move at 90 degrees, the operation is considered as a success.
• If after 6 month, the joint is still not recovered, the patient will go to therapy.
This system has many problems:• Some people don’t exercise at home (lack of motiva-
tion, lack of confidence, don’t remember the exer-cises, don’t think about it, etc.)
• Some people work out too much and risk to hurt themselves (over-motivation, body limits unaware-ness, etc.)
• If a movement is done in a wrong way or with too much amplitude, the joint can dislocate or break again.
• If physiotherapy is done too late after the surgery, its efficiency is very low.
Globally, the existing system minimizes the direct costs (equipment, medical visits and physiotherapy). How-ever, because it’s efficiency is quite low, it has many additional costs like additional physiotherapy sessions, personal assistance for non-self-contained people, etc.
simplified scenario of recovery after a serious joint fracture
Innovation Context
external fixation or
Internal fixation (surgery)
passive training
(low-stress workouts)
active training with
physiotherapist
Everyday life
Active training alone
Hospital Home
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Global Solution
Monitoring Our solution is to imitate some aspects of the therapist to give patient reassurance that he is being looked after, knowledge what to do when he is exercising, motivation to do the exercises thoroughly and all of that in home environment. We achieve it with sensors that are placed on the body.
Devices Sensors can’t do anything reasonable by themselves - they need some interpretation. So our solution consists of three different parts. Firstly, as mentioned there are sensors, secondly there is a device that is with you all the time (even when you are sleep-ing) to monitor your physical activity and warn you when needed. Thirdly there is a device that will assist you when you are working out - it has more specific capabilities to help you along the way.
Pre-Concepts Nb: “Doctor” can designate a physi-otherapist or a nurse
Concept 1: Plasters and frequent visitsSensors are placed on the body with a kind of plaster, this is done by a doctor to ensure the right placement. The doctor will set up the devices and teach patient to use them. Plasters are thereafter changed every 1 to 2 weeks during visits to the doctor. Sensors and bracelet are replaced with new ones that have charged battery. Data stored in the bracelet is transferred over blue-tooth to the doctor’s computer where it is analysed by a computer program which is in turn overviewed by the doctor. Doctor receives information about patients’ activity between the visits, wrong movements made by patients and joints’ movement amplitude and can give suggestions and new workouts directly face to face.
Concept 2: Strap/pants and distance monitoringSensors are placed on the body with several straps or pants-like things, by the patient him/herself. Device is removed every night and re-applied every morning. Sensors are big enough to be feeled and put in a good position (more space for electronics). Data is sent auto-matically to the doctor via phone system. Doctor analy-ses the data from his/her office, then can call or meet the patient if needed. Doctor can be alarmed in case of emergency (fall etc). Device is set up first time by the doctor and thereafter by the patient him/herself. Feed-back about current situation is received over phone or in case of a very serious problem the patient is called to the hospital for an emergency visit.
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Concept 1: Plasters and frequent visits
Concept 2: Strap/pants and distance monitoring
Wash the device Don’t need to be washed
Washable waterproof and temperature resistant Not usable during washingsensors must be removable from strapsPossible to not wash it often?
Take a shower/bath PossibleNeed to be waterproof which is expensive if bathing should be included
Has to be removed
Go to toilets No changes Straps: no changesPants: Need to be removed
Comfort SweatNeed to be flexiblePainful when removedcan be removed with solvaint
Straps: need to be tightPants: ok
Battery all components must be really power efficient
Seems ok, especially with pants (1 battery and 1 transmitter)Extra power to send energy
Accuracy Good because applyed by the doctor/nurseCan move if skin is flabby
placed in non flabby places
Straps: Difficult to put accuratelyCan move afterwardsPants: ok for the positionGood stability
Aesthetics ok more visible
Price and time for doctors
MediumCan be combined with distance monitoring if no battery problem
Depends of the needsDoctor needs to file a report even if monitoring from distance
Efficiency Long time before feedback of doctorCan be combined with distance monitoring if no battery problemDirect contact with doctor immediate feedback
Doctor receives the data quicklyDon’t see the patient directly
Communication Good and predictable Few direct meetings less confidence
Amount of work and difficulty for patient
None Every morning and evening
Legend:Good BadNeutralPossible solution Possibility to
correct the position when it is disturbed
Can´t change immediatelyPainful to take off
difficult if it is under dressing
Physical conditions of patient: memory, vision, balance, movements
good, because I can’t feel it all the time/ possible to forget that you have it on
Pants: difficult to put on, to correct them( balance and possibility to turn the body, stomach aloud not); fingers will not move well; forget to put onStraps: difficult to feet down the leg ( balance, fingers will not move well, stomach aloud not), difficult to worship; forget to put on, cant see the connection marking
How it feet with dressing
Very well- possible to put on as pants , so as tights (women)
Pants: impossible to compose with other dressing(type, colour, boots- stout body)Straps: difficult to put on with tights; connections remain in the fabrics
How it fit with the body
Doesn’t disturb body movements;
Pants: uncomfortable - can’t change the pants if its too warm. It is needed to put on and off mornings and evenings- I don’t want to do it again , because it is painful and difficult; should be right size; it supports body- helps to moveStraps: scale of sizes; if it is not well placed it can slip down or move to the wrong position; disturbing to lie down or took of for resting time- squeezes and disturbs because of the thickness of the fabric);
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Possibility to correct the position when it is disturbed
Can´t change immediatelyPainful to take off
difficult if it is under dressing
Physical conditions of patient: memory, vision, balance, movements
good, because I can’t feel it all the time/ possible to forget that you have it on
Pants: difficult to put on, to correct them( balance and possibility to turn the body, stomach aloud not); fingers will not move well; forget to put onStraps: difficult to feet down the leg ( balance, fingers will not move well, stomach aloud not), difficult to worship; forget to put on, cant see the connection marking
How it feet with dressing
Very well- possible to put on as pants , so as tights (women)
Pants: impossible to compose with other dressing(type, colour, boots- stout body)Straps: difficult to put on with tights; connections remain in the fabrics
How it fit with the body
Doesn’t disturb body movements;
Pants: uncomfortable - can’t change the pants if its too warm. It is needed to put on and off mornings and evenings- I don’t want to do it again , because it is painful and difficult; should be right size; it supports body- helps to moveStraps: scale of sizes; if it is not well placed it can slip down or move to the wrong position; disturbing to lie down or took of for resting time- squeezes and disturbs because of the thickness of the fabric);
Conclusion We decided to go with the plaster concept, mainly so because of the benefits when wearing it and the fact that it’s less demanding for the patient. The plaster concept got even stronger when feedback from our fam-ily doctor came back saying that even when they monitor from the distance they still must file the report, so there is no time benefit for doctors with distance monitoring, if anything then the time will be increased because of the denser monitoring cycle.
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Usability Patches Patient is wearing patches all the time, these are applied and changed during medical visit that hap-pens roughly once every month. The patches are invis-ible under clothes, they withstand showering but bath-ing and swimming is not allowed during recovery period (this will exclude water therapy). Patches are made from fabric that lets skin breathe but makes the patch more durable. When a patch has been applied on skin for a month it could be stuck quite toughly so solvent can be applied to remove it.
Bracelet & Tablet Usability qualities of the bracelet (device that is always with you and is meant to monitor your overall activity) and tablet (specialized for exer-cising) are made to meet the possible physical changes of aging. Typically these are diminished vision, vary-ing degrees of hearing loss, hand eye coordination and psychosomatic impairments including difficulty with small motor coordination. Important factor to follow is the emotional and physical stage after surgery or injury rehabilitation in hospital.
Emotional qualities of bracelets and tablets usability:
safetymotivationassuranceindependenceself-confidence
Usability milestones of bracelet:
• uniformly understandable display data• easily manipulative grasp of the bracelet, so it is
easy to put it on and take it off (see image on the facing page)
• antibacterial material• good contrast of display colors• visual, sound and vibration alarms provide efficiency
in the different physical conditions of the elderly users
• is applicable with one hand
Benefits of bracelet:
• black-white and two warning colors • uses 3 different possibilities of alarm: visual, sound
and vibration - they all work simultaneously and complement each other to give clear understanding of the situation
• it has also low battery indicator (emergency only, normally battery is replaced in hospital)
• easy to put on and take off because of material of the strap and system of the clasp what is broaded on the end so that it is impossible to pull it out of the buckle
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Characteristics of tablet:
• has two working positions: standing and lying for various using patterns
• doesn’t have a battery and only needs to be plugged in to operate
• display orientation will change according to the posi-tion of the device
• two buttons to use: on/off and pause/play• exercises are displayed as video, these are the same
videos that are already in use at the rehabilitation centres
• speaker and warning signs let the person know about too fast and wrong movements, also voice command is played when proceeding to the next exercise
The bracelet uses Velcro to open and close easily. The end of the strap is bigger than the buckle so the bracelet never completely opens, and is therefore easy to slip on the wrist.
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17
18
19
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The clock is ringing Ants opens his eyes, he puts one leg over the bedside to stand up. Something on his night-stand goes BEEP-BEEP-BEEEP... he hears it almost every morning, it is an alarm saying he bends his leg to a dangerous position. As the sound isn’t violent he knows that he is in the safe zone and that this is just a reminder. He raises to sitting position, picks up the bracelet that doctor gave him after his hip surgery and fastens it on his hand.
Over last couple of weeks Ants has developed a habit of going to the market place with his wife. Doctor suggest-ed him to walk daily and going to marketplace is a nice and pleasing outcome of trying to fulfill that command. As the weather is nice and their house isn’t far they de-cide to walk back. In front of the house Ants is looking at the bracelet that doctor gave him and he smiles. The watch shows that he has already done half of the daily physical activity required.
Storyboard
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It is time for everyday workout. Well, it isn’t so much an exercise as it is just bending practice, he thinks. At the last meeting the doctor showed him some exercises that would be best performed next to table. As always he turns on the device that shows him exercises the doctor described. The display on the device starts to glow and plays a video clip of the exercise. Ants is already famil-iar with the exercises so he isn’t looking at the screen so much because he knows the movements and the device tells him with nice voice when he is doing something wrong. After some repetitions device says: “That’s enough it will do. Lets move on to the next exercise” and the video showing next exercise starts. Right then telephone rings! Without hesitation he pushes one of the two buttons on device, which pauses and answers the phone, it was his daughter checking his progress on recovery. After call ends he walks back to the table and turns on the device, screen starts to glow and it starts to play the same video it was prior to shutting off.
In the evening Ants decides to take a shower. As he undresses he puts the bracelet on top of the washing machine. As in their apartment shower and bathtub is joined, getting under shower is hard work for someone who is recovering from hip surgery. The bracelet seems to agree as it starts vibrating and beeping vigourosly a few times during his “mountain climbing”. This might be the most extreme point of the day regarding to his recovering limb. Ants thinks that he might avoid show-ering altogether when there weren’t this little helper.
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Everyday life
Situations Vibration alarm Sound alarm Visual alarm Screenmorning, wake up,
beginning of the day
wrong movement, too large amplitude
of movement or too fast
starts with low interval impulse,
grows more vigorous as the limit gets
closer.
starts with low interval impulse,
grows more vigorous as the
limit gets closer.
alarm lightoutside the screen.
alarm lightoutside the screen
amount of activity is too close to the limit
Limit is achieved
2x beep 2x vibration impulseAmount of activity
is to less
2x beep 2x vibration impulse
Baracelet is not on the hand
steady signal steady alarm lightoutside the screen
steady alarm lightoutside the screen
Stay a long in wrong position or
fall down
stop after a while stop after a while stop after a while stop after a while
bracelet’s interface
bracelet’s interfacebracelet’s interfacebracelet’s interfacebracelet’s interface tablet’s interfacetablet’s interface
situations Sound alarm vibration Visual alarm
screen Voice on tablet
Screen
start exercising
wrong movement, too large amplitude
of movement
starts with low interval
impulse, grows more vigorous as
the limit gets closer
starts with low interval
impulse,grows more vigorous as
the limit gets closer
alarm lightoutside the
screen.
alarm lightoutside the screen
too fast movement
the end of exercises
depends on how much is done
too much is done
2x beep 2x vibration impulse
off off
too littleis done
2x beep 2x vibration impulse
off off
stay long in a wrong position or fall down
stop after a while
stop after a while stop after a
while stop after a while
23
Working-out
bracelet’s interfacebracelet’s interfacebracelet’s interfacebracelet’s interface tablet’s interfacetablet’s interface
situations Sound alarm vibration Visual alarm
screen Voice on tablet
Screen
start exercising
wrong movement, too large amplitude
of movement
starts with low interval
impulse, grows more vigorous as
the limit gets closer
starts with low interval
impulse,grows more vigorous as
the limit gets closer
alarm lightoutside the
screen.
alarm lightoutside the screen
too fast movement
the end of exercises
depends on how much is done
too much is done
2x beep 2x vibration impulse
off off
too littleis done
2x beep 2x vibration impulse
off off
stay long in a wrong position or fall down
stop after a while
stop after a while stop after a
while stop after a while
bracelet’s and tablet’s interface
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Technical working
BraceletPatches
Tablet
Soundalarm
Interface
MovementWiredWireless
Visualalarm
Vibrationalarm
1
2
3
4
5
6
6
6
7
87
9
10
The figure below describes the interactions between the patches, bracelet and tablet electronic components.The patches capture the body movements with the mo-tion sensors (1) and send it to the bracelet via bluetooth (2).The collected data are then processed by the bracelet microcontroller (3), to calculate the joint angles. These angles are saved in the bracelet memory (4). The brace-let display changes according to the quantity of move-ment registered (5). If a problem is detected by the microcontroller, the alarms will work (6).When the user is working out, the LCD screen displays a video of the exercise, which is stored in the tablet memory (7-8). The exercise is chosen according to the settings of the bracelet (4-3-7-9). The data processed by the bracelet are used by the tablet microcontroller to command the speaker (3-7-9-10).
25
Motion sensor To measure movements, several kind of electronic components can be used:• Accelerometer and gyroscopeThey measure respectively the linear and rotational ac-celeration. To measure a position, it should be calibrated (refer-ence position and sensibility). Also, they have a limited measure speed; if this speed is exceeded, the reference position has to be set again.• Infrared DEL and cameraThis solution uses special camera to follow the move-ment of infrared DEL (For instance in the Nitendo Wii™). Because the camera is external and should always point at the DEL, it’s not suitable for our appli-cation.• Incremental encoderIt measures the angular position or motion of an axle. Because it measures the position only around an axle, it’s not suitable for complex joints like the hip, which can rotate in every direction.• Electronic compassAn electronic compass uses the magnetic fields to know its orientation. By calculating the difference between the angular position of the two compass, it’s easy to measure an angle.In this way, the reference is always the same for every sensor, so the measures are reliable.These components are cheap (~2€), small (~15mm3) and consume little energy (~100µA in normal mode, 1µA in sleeping mode).An electronic compass in each patch will be used to measure the joints’ angles.For instance, the STMicroelectronics LSM303DLHC could be used (see Appendix VI)
Wireless connection Because the bracelet is always close to the patches, and people work-out near the tab-let, the distance range is approximately 5m (plus secu-rity margin).The amount of data is very low (few kbit/s).The Bluetooth v4.0 with low energy technology suits very well.
Bluetooth v4.0 low energy characteristics:
Bluetooth low energy chip
Distance range 10 to 60m
Bit rate ~200 kbit/s
Current consumption 15.8 mA (0.001mA in sleeping mode)
Size 6mm x 6mm x 0.85mm
Price ~2€
Patches
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Autonomy calculation Because the patches will be changed every 3-4 weeks only, they should have this autonomy at least. The patches are worn all the time, so their electronic part (including the battery) should be as small and lightweight as possible. For this reason, it is important to optimize the energy consumption.• Bluetooth consumption:Single connection event of BLE: 2.3 ms@10Hz active time: ~2%The average current consumption during a single con-nection event: ~10.655 mASleep current: 0.001 mA
=>Average consumption: [ (1000 ms – 2.348 ms)*(0.001 mA) + (2.348 ms)*(10.655 mA) ] / (1000 ms) = 0.026 mA(Sleeping mode / Normal mode)
• Compass consumptionCompass average current consumption: 0.11 mA• Global autonomyCoin cell battery* nominal capacity: 550mAh550mAh /(0.026mA + 0.11mA)= 4044h4044h/24h = 168,5 days = 24 weeks
=> A patch can have a long enough autonomy with a very small and lightweight battery.*A coin cell battery is used for calculations as an ex-ample. The final device could use any kind of battery (disposable or rechargeable). The example battery has following characteristics: 3V, 13mA, 24.5 x 5.0 mm, 6.2g, 0.08 - 0.16 € / Piece.
Wireless connection See “Technical working/Patches/Wireless connection” page 25
Microcontroller The bracelet microcontroller is used to:• Calculate the joint angle from the sensors data• Control the bracelet alarms• Control the bracelet display• Store the data in the bracelet memoryBecause the required speed is very low comparing to existing microcontrollers, the bluetooth embedded mi-crocontroller could maybe be used.
Memory The bracelet memory should store:• The bracelet firmware• All movement data between two medical visits• The reference of the exercises gave by the doctor• The limit angle settings
In this way, during a medical visit the physiotherapist can download the movement data and set up the system via bluetooth.
Activity display The display should be easily readable in all conditions. A liquid crystal display (LCD) is not readable if the light level is too high. Also, the back-light of an LCD screen consumes a lot.For these reasons, an electronic paper (E-ink) will be used.
Bracelet
44
5414
27
The main advantages are:• Electronic paper uses natural light. So it is visible
even in difficult condition (except dark), just like usual paper.
• The energy consumption is very low (and null when the display remains the same).
• Cheap (a few euros)
The E-ink is usually only black and white (color screens exist but are expensive). Because the displayed colors are constant (orange and red), some color filters will be placed above the display. It will color the white parts of the display, but will remain almost invisible on the black parts.
Visual alarm For the visual alarm, a LED light is more suitable than the E-ink, because it is more «ag-gressive». To include the led light in the E-ink display, there are several possibilities:• Because the electronic paper can be translucent, a
backlight can be placed behind (the display back-ground would become white for a better visibility).
• A light can be placed around the display (the display background would also become white for a better visibility).
• A hole can be drilled in the center of the display to insert a light (the E-ink would still work).
Bracelet display
Filters can give color to electronic
paper
Visual alarm with light around the
display
Visual alarm with light in the center
of the display
Visual alarm with backlight
28
Vibration alarm The same kind of vibration motor as used in cellphones is suitable. They are cheap, small, lightweight, etc.An example is the “Precision Microdrives 310-103”
Sound alarm The alarm should be loud enough to be heard in a noisy environment. A powerful enough speaker would be big, heavy and power consuming.The alarm will then be a simple polyphonic “beep”.In order to not be too loud in more quiet environment, a small and cheap microphone will be used to measure the environment noise level, and then adjust the alarm level.
Wireless connection (Bluetooth low energy) See “Technical working/Patches/Wireless connection”page 25
Memory The tablet memory will store every exercise demonstration. Each exercise has a reference, so the bracelet can control which exercises will be displayed.It also stores the vocal records used by the speaker.
Microcontroller The tablet microcontroller controls the screen and the speaker. It also counts the exercise movements with the measured joint angles.
LCD display The tablet will be used indoor, and will be mains-operated (plugged). A color LCD screen will be used to display the exercise demonstration. Indeed, the light and consumption are not problematic in this case.
Speaker To give clear information, the tablet will use a recorded voice. Normal speakers used in multimedia equipments are suitable.
Tablet
270
201
76
Precision Microdrives 310-103
29
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30
PatientMedical staff
Device producer
Surgery
Bone fracture
Surgery
Beginning of rehabilitationIntensive care
Get the sensorsPut the sensors on
Learn how to use the device
Teach how to use the device
Everyday life
Medical visit
• Gives feedback• Learn new
exercises and practise
• Remove sensors• Download and
analyse data • Put new plaster• Physical check• Change watch
battery• Set-up (Angle
limits, exercises and speed)
• Teach new exercises
Working-out
Send discharged sensors
Device production
Device supplyNormal logistics
• Receive sensors• Test battery• Recharge
battery• Pack sensors in
new plasters• Ship back
sensors
Final medical visit
Give back the watch and external
device
• Remove sensors• Download and
analyse data • Physical check• Recovery
validation• Advices
Tech
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Everyday life
Working-out
Tim
e
Service blueprint
31
Further developments
The project has a lot to be developed, for instance we left aside the doctor’s side of the information flow. We included some information but the area is lack-ing deeper research and development. Similarly we didn’t go into further details with the electronics partly because our team lacks the competence and partly because the project will be taken further by Peeter Lump - a master student from the depart-ment of mechatronics who will prototype the neces-sary components as his master thesis. Also rehabili-tation nurses in Viimsi hospital offered their help with finding patients for testing if the project reaches prototype stadium. Further development should also take place on graphical interface part - there are already many changes that could improve the performance on the interface level that didn’t fit to the report.
It seems that the project timing was very good, as a few key components that were crucial for project’s success were released after the start of this project. For that reason high activity can be expected in that part of the field this year. We believe that in a few years personal monitoring will become highly acces-sible. It is possible today and will be more effective tomorrow. Technical development is definitely head-ing that way.
Conclusion
ReferencesTechnical
Bluetooth low energy (05/12/2011) http://www.bluetooth.com/Pages/Low-Energy.aspx
Electronic Paper Displays (27/12/2011) http://www.eink.com/
Vibration Motors - Precision Microdrives (24/11/2011)https://catalog.precisionmicrodrives.com/order-parts/product/310-103-10mm-vibration-motor-2-7mm-type
Existing
Movea - Joint Assessment (18/11/2011) http://www.movea.com/applications/e-health-and-wellness/joint-assessment
Motion trackers and motion capture systems for biomechanics research - Xsens (18/11/2011) http://www.xsens.com/en/movement-science/mtw
Up by Jawbone | Band + App Inspires Healthy Living (09/12/2011)http://jawbone.com/up/product
Medical
Quality of life related to fear of falling and hip fracture in older women: a time trade off study ; G Salkeld, I D Cameron, R G Cumming, S Easter, J Seymour, S E Kurrle, S Quine (BMJ VOLUME 320 5 FEBRUARY 2000) “Forget-me-not: Long-term Post-operative Care in Hip Fracture Patient” presentation by: Jay Magaziner, PhD, MSHyg
32
Home-Based Multicomponent Rehabilitation Program for Older. Persons After Hip Fracture: A Randomized Trial (Arch Phys Med Rehabil Vol 80, August 1999 ) A SOCIAL PORTRAIT OF OLDER PEOPLE IN IRELAND (Government of Ireland 2007) A healthier elderly population in Sweden! Göran Berleen (ational institute of public health – swe-den 2004) PREVENTION OF HIP FRACTURE IN ELDERLY PEOPLE WITH USE OF A HIP PROTEC-TOR (The New England Journal of Medicine VOLUME 343 NOVEMBER 23, 2000)
Randomised factorial trial of falls prevention among older people living in their own home (BMJ 2002)Lesley Day, Brian Fildes, Ian Gordon, Michael Fitzharris, Harold Flamer, Stephen Lord
Fear of Falling After Hip Fracture: A Systematic Review of Measurement Instruments, Prevalence, Interventions, and Related Factors (2010, The American Geriatrics Society)
Older adults’ perspectives on home exercise after falls rehabilitation: Understanding the impor-tance of promoting healthy, active ageing Helen Hawley (Health Education Journal September 2009 vol. 68) SOCIAL AND HEALTH PROBLEMS OF THE ELDERLY Ljiljana Pesic (Acta Medica Medianae 2007)
Joint fracture treatment (04/01/2012) http://bonesfracture.com/joint-fracture-treatment-joint-bone-fracture-surgery-fractured-joint-healing-time-symptoms-and-recovery/
Tools
Workshop attended on 26.09.2011 and venue Tallinn University of Technology, room V 215Title of workshop: System design for sustainability and servicehttp://www.lens.polimi.it/index.php?P=lr_upload_course.php&ID=MLYUUXUFON20090708202156&DWNL=Y#
Tests and interviews
dropbox/ report/ appendixes/tests results
dropbox/ report/ appendixes/elders view
33
Appendixes
Opinion of 3.elderly person ( women ) in 65, 76 and 90 years about equipment, comparing plasters and pants, wearing and use :
• All worried about how to remember exercises they should to do: what exercises, how much and how often
• Liked idea of plasters more, because it is simply to wear, possible to compose with other dresses
• Plasters, because it is not needed to put on and take off
• 2. of them (90 and 76 ) was worried about how carefully they should wear plasters for not making wet or not to take off accidentally
• Liked watch idea very much, because it is like a milestone of remembering, possibility to see how much exercises have been done
• But worried about when the watch let them know about wrong movement , how they will get know what position exactly was done with wrong angle or direction
• Worried about watch to put on and off because fingers don´t move so good ( 76, 90 )
• About the display of watch to be clear to view and to understand, because they afraid to do something wrong with electronic equipments
• Liked alarm and vibration of watch, because it seems better when both signals works at one time
But:All of them thought that this is a good idea to be controlled by equipment and
interaction with a doctor or a specialist
Plasters- simple to wear, possible to compose with other dresses
System-how to remember exercises
Plasters- it is not needed to put on and take offhow carefully they should wear plastersWatch- like a milestone of remembering, possibility to see how much exercises have been done
when the watch let them know about wrong movement , how they will get know what position exactly was done with wrong angle or direction
Alarm and vibration of watch- better when both signals works at one time
watch to put on and off because fingers don´t move so good ( 76, 90 )
System-it is a good to be controlled by equipment and interaction with a doctor or a specialist
watch to be clear to view and to understand, because they afraid to do something wrong with electronic equipments
Appendix I: Findings among older people
34
Bracelets interface test results:what is important for user
Visual alarm
Sound alarm
Vibration alarm
Limit set by doctor
Wrong movement
control
Wrong movement
control
Limit set by doctor, battery
Wrong movement
control,Over limit
Wrong movement
control
Limit set by doctor, battery
Over limit Wrong movement
control
Bracelets interface test resultsquestion answer
Should I wear a bracelet all the time ?
Yes, it is the main idea
Will it possible to remain me I should do exercises ?
It is possible, but it will be complicated to compare all alarms
When I should check my results: during the day or on the end of the day ?
It is possible to check during the day or in the end
What I`ll see on the bracelet screen after I do the wrong movement? What I should do next, push some button ?
Visual alarm as a light outside the screen. It is not needed to push the any button (not exist), the signal will stop if the position will change
Will I see next day yesterday achievement or start with new?
Start with a new one
Appendix II
Appendix III
35
Tablet interface test resultsquestion solution
How can I start the exercise video ?
Just push the on/off button
How can I stop and continue ?
Push the pause/play button
If I do wrong movement will I see info on the screen?
Yes, a red triangle and a voice declaring it
Will I see the certain place on the screen I did wrong movement?
No, it will be just video of exercises, not animation of real movements
Does the video stop after I do wrong movement that I may then continue?
Video stops with voice alarm and red triangle and continue itself after position is changed
Usability of bracelet and external device
Functional qualities “ Soft “ qualitiesSound and vibration alarm Safety: wrong movement
controlExercises menu- introductory video, reminder
Independence:`”I may do it by myself without asking “
Activity results will be collected independently
Assurance: results will be analysed by specialist
Alarm when the limit is exceeded
Encouragement: allowed limit set by the doctor
Activity screen Self-confidence: “ I can move and see results “
Appendix IV
Appendix V
36
Preliminary data
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
April 2011 Doc ID 018771 Rev 1 1/42
42
LSM303DLHCUltra compact high performance e-compass
3D accelerometer and 3D magnetometer module
Features■ 3 magnetic field channels and 3 acceleration
channels
■ From ±1.3 to ±8.1 gauss magnetic field full-scale
■ ±2g/±4g/±8g/±16g selectable full-scale
■ 16 bit data output
■ I2C serial interface
■ Analog supply voltage 2.16 V to 3.6 V
■ Power-down mode/ low-power mode
■ 2 independent programmable interrupt generators for free-fall and motion detection
■ Embedded temperature sensor
■ Embedded FIFO
■ 6D/4D orientation detection
■ ECOPACK® RoHS and “Green” compliant
Applications■ Compensated compass
■ Map rotation
■ Position detection
■ Motion-activated functions
■ Free-fall detection
■ Click/double click recognition
■ Pedometer
■ Intelligent power-saving for handheld devices
■ Display orientation
■ Gaming and virtual reality input devices
■ Impact recognition and logging
■ Vibration monitoring and compensation
DescriptionThe LSM303DLHC is a system-in-package featuring a 3D digital linear acceleration sensor and a 3D digital magnetic sensor.
LSM303DLHC has linear acceleration full-scales of ±2g / ±4g / ±8g / ±16g and a magnetic field full-scale of ±1.3 / ±1.9 / ±2.5 / ±4.0 / ±4.7 / ±5.6 / ±8.1 gauss. All full-scales available are fully selectable by the user.
LSM303DLHC includes an I2C serial bus interface that supports standard and fast mode 100 kHz and 400kHz. The system can be configured to generate interrupt signals by inertial wake-up/free-fall events as well as by the position of the device itself. Thresholds and timing of interrupt generators are programmable by the end user on the fly. Magnetic and accelerometer parts can be enabled or put into power-down mode separately.
The LSM303DLHC is available in a plastic land grid array package (LGA) and is guaranteed to operate over an extended temperature range from -40 °C to +85 °C.
LGA-14 (3x5x1mm)
Table 1. Device summary
Part number Temperature range [°C] Package Packing
LSM303DLHC -40 to +85 LGA-14 Tray
LSM303DLHCTR -40 to +85 LGA-14 Tape and reel
www.st.com
Appendix VI
