About my blog

The aim of the ITD course (ID4220) at the Delft University of Technology is to provide Design For Interaction Master students with in-depth theoretical and practical interaction design knowledge to help develop future products based on user-product social interaction. ITD proceeds through a sequence of iterations focusing on various aspects of the brief and the design, and culminates in an experiential prototype.

This blog is managed by Walter A. Aprile: please write if you have questions.



De meningen ge-uit door medewerkers en studenten van de TU Delft en de commentaren die zijn gegeven reflecteren niet perse de mening(en) van de TU Delft. De TU Delft is dan ook niet verantwoordelijk voor de inhoud van hetgeen op de TU Delft weblogs zichtbaar is. Wel vindt de TU Delft het belangrijk - en ook waarde toevoegend - dat medewerkers en studenten op deze, door de TU Delft gefaciliteerde, omgeving hun mening kunnen geven.

Posts in category tagging2

This is the final movie of Watcho!

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Exhibition & Concept

exhibition was fun! Thank you all for coming, we had a good time demonstrating
and explaining our concept to you all. In addition, we would like to thank you
for your feedback as well. As reward, we will now show you a few pictures of
yesterday. These involve the prototype, the exhibition layout, the
demonstration and explanation.

this we would like to post our final concept as a whole again, so you are able
to reread it as often as you want: The Watcho is a tool which enables
communication between an elderly and his nearby caregiver. Both of these
persons have a watch which communicates wireless. It communicates two aspects:
1) the activity of the other person. With this aspect people will know when the
other is busy doing exercises for example, or one could see whether the other
is still awake at 22.00. This activity is visualized on a range of 0 to 3 light
zones which will glow, starting from the bottom of the watch). 2) the
communication between both parties. This is done via two button which
individually correspondent to either a blue or red light. When pushing the
button short the light at both watches will start to glow, now both of the
watcho-carriers are able to turn it off with the same button. When pushing the
button for longer than 3 seconds, an vibration motor will start in addition to
the glowing lights. This indicates a more important message. The messages of
the communication are not pre-defined. This means that the involved parties
could make up their own meaning and change it whenever they want. For example:
red is ‘please do not call, I’m in an important meeting’, or red is ‘I don’t
feel so good today’. Blue could be ‘I have come home okay’.

Our last friday

Another prototyping day

Today was again
full with programming and making the prototype. At this moment the Xbees are
programmed with the first patch. As soon as the hardware is ready we will be
able to test the program and the get the question answered whether this part of
the prototype is working. On the other hand, our programmer is busy with the
accelerometer and translating its input towards a three LEDs, which have to
visualize the amount of movement of the other watch.

our maker is busy making the real prototypes. Still a lot has to be done, so
working hard also means working at home. Only this way we could have a good
working prototype at the exhibition day on the 29th of June.

Besides the
prototype we are busy with preparing the rest of the exhibition. A explanatory video
is been made, which would be shown within the exhibition since the watches are
too small for a demonstration among a large amount of people. Also posters and
flyers are prepared for this exhibition.  The most important aspect of the exhibition
still has to be discussed thoroughly among the team members. This contains
creating the correct context and atmosphere within our exhibition space. Only
this way will our prototype get the full and correct amount of attention.

Prototype day

Today we had the will power, abilities and tools to work hard on our project. We have split up the tasks for an efficient workday. Reflecting on last Friday, we had some time to make up for our missing time. Therefore we have not, and will not, only work on this Friday.

The two programmers divided the tasks such that one is programming the usage of the accelerometer and translating this data to a simple LED feedback. The other programmer is trying to get a wireless connection between the two watches working. The programming of this is rather different from the previous ones; therefore a change in way of thinking is required to make such a system working. Now one is able to turn on and off a LED via typing a ‘1’ in some kind of chat screen. Both programs have to be extended to create one working prototype.


The maker and his ‘help’ were busy with putting the electronic component in produced watches. They have one watch almost completed, containing now the LEDs and buttons in the way it still looks like a ‘normal’ watch. Due to component within the watch several elements got a different position. We figured that for the exhibition we have to make a digital illustration of our watch as well.This way we can show that we gave the interaction with the watch a good thought. The same goes for the rest of the interaction, containing the elements. Today one of the team members put everything on paper like we have mend to make our concept. This way we have a solid basis for the exhibition,paper, and communication within the team.

The fifth and last team member got herself busy by thinking out the scenario of the final video. By beginning early, it will be easier to be critical towards the video and change it in such a way that it fits the idea we want it to be.
All in all, we have still loads of stuff to work on, however we have also quite a lot finished. This gives us energy to complete this project with a good working prototype.


Today we hit a glitch in the project. We still hadn’t got the tools to work further on the programming. This is due to a longer delivery time and a broken accelerometer without having a backup one. This means that our project had a moment of a pause. We were still be able to work on the final paper and preparations for the exhibition. However this is not yet a 5 man job. So we have to catch up the missing time later this week. Even with these setbacks, we did make project related items. These are a logo for the product, the watcho. And we made a corresponding font to emphasize difference between ‘elderly’ and ‘child’ within the presentation, exhibition, movie, scenario etc.  


[Find the missing letter in our, until now, 25 characters-font] 


Baby steps to the Final prototype

This week we would get feedback on every bit we have done so far. With approval we could start making our final prototype and the correspondig exhibition. In the end we can say that we are working good and into the right direction. We have made ofcourse good and bad decisions. However, the good choices are the ones which are more important in this course. For example we chose to make our prototype with an Arduino by ourselves, instead of using a produced watch which could be programmed in every way. The Arduino usage is better for us since it is linked to our personal goals and development. On the other hand, our concept could lack on the feasibility area. Why do people want to use such a watch when there are other related products on the market? In addition, is it really related to our target group, or does it fit better to users with an emergency job, like the police? This is something we have to prove for ourselves with user tests.

Besides getting feedback we took some baby steps in making the final prototype. We indeed got the green light to order our desired products, like the watches. Some of us already started working on the documentation in the direction of making the final paper about our product. And the previous prototype has to be translated in another programming language. Since it was written in the MAX5 language, and we are going to use an Arduino for the final prototype. In the end, we have had again a nice day of work behind us. And we also have still a lot of work to do before we have to present our prototype on the 29th of June.  

User Testing and Further


For the first User study a paper prototype was used to test it with family. Due to inconvenience with the technology we were forced to use a paper prototype. Still our approachwas to let them play with the prototype, change it in the meantime and explain its function when time evolves. With this approach we discovered more of the personal meaning of this watch, and in which direction the possible user are thinking at this moment.


Woman, 52:

  •           Clearer buttons, this range is too large, this could be directed maybe.
  •           On and off is fine for button functions.
  •           I only want to know whether my mother is out of bed and that she’s still here. Only presence is necessary, no details.
  •           I like the watch to be discrete, and not noticeable by others. This means not too much light in sight, should be integrated within the watch.
  •           The watch has to look like a normal watch, so no weird colours or lights.
Man, 54:
  •           I have to understand it, 1 button is enough for me.
  •           What will happen if I’m not wearing it?
  •           Maybe it is nice that you can apply it to one’s normal watch, so you won’t need aspecial one.
  •           Negative versus Positive button?
  •           The buttons have to be clear for the older people.


  •           Will worry immediately when there is little activity, after weeks patterns are learned, small details are more noticeable and sooner a reason for contact.
  •           One button will be the alarm button for both sides, needs to look like an alarm (red).
  •           One button with different temporarily meanings.
  •           Watch may not look special.
  •           The buttons should be easy to handle, due to the decreasing motor skills of the hands of elderly.


After the user studies, we went to our client todiscuss our concept more thoroughly.

  •           Emergency option is a logical implementation.
  •           Interaction still a bit poor, try to look further than just two buttons to create more options for meaningful tags.
  •           Activity more at ‘this moment’ rather than ‘over 15minutes’, or more, because of the short activities. An average of a longer time will eventually give always the same expression.
  •           Extra information may not draw too much information, for important messages vibration could help the users to react immediately.


Working towards the final exhibition, we will first plan what to show before we start prototyping. Our product has many disadvantages for an exhibition, for one it is small (making it difficult to let many people experience it at the same time). It requires a learning curve and a long duration before fully knowingthe product. And it is used at two different places.

We decided to make a watch with the minimal interaction, but working wireless.Here two visitors can use the watches, and while beaming their interactions we can show more people what happens. We also create two different contexts,emphasizing the different locations of usage.

Programming over the last few weeks


During the design process, different programming was necessary to support the different concepts. With Max the software is totally different in comparison to verbal programming. It took some effort to understand Max.

Concept 1 (Simon says hack)

This concept was made from the Simon game. The idea was to make a game for grandmother and grandchildren. The persons could turn on a light somewhere inthe house, the other person can turn it off when the person is there. This concept required a multi-way switch. This is used a lot with stairways to turn on or off the light. Two switches are connected so you are able to switch one light on and off with two buttons.


In the figure above you can see part of the patcher. It consists of 4 of these withdifferent inputs and outputs. The switch on the left is switched on by one person, the light will turn on and the other person can turn it off. The trigger bang is needed by the sum because only then the outcome is computed (right inlet does not give a bang, but is computed when the left inlet receives a bang. The % 2 box makes sure that when both of the switches are high, thatthe outcome is low.

Concept 2 (Intelligent fridge)

In the second concept different sensors were present in the house of the elderly. One sensor (button) was under the doormat. The other sensor (button) was at the coat hanger.This way it could be measured whether a person was leaving or entering thehouse.

In the figure above the patcher of the software is shown which shows two different messages depending on whether a person is leaving or entering the house. First, each sensor get a number assigned. The zl group 2 makes a list of 2 numbers and when the he has two numbers it flows to the unpack. The number which comes out first determines which message is shown. The select takes care of this. However, if one sensor is pressed twice, there should be no message at all. Therefore if both numbers are summed up, the outcome should be 3. Only then an answer shouldbe given. Unfortunately the patcher does not work well. It gives outcomes whenone sensor is pressed to times. Before the presentation there was no time to fix this, after the presentation the concept has changed.

Concept 3 (Watcho, watching grandma)

In this concept there is a part which measures the activity and a part which is acommunication tool between the caregiver and the elderly.


For this part the multi-way switch is used again here but there is some improvement. With the togedge the pressing and releasing of the button are separated. With some testing the releasing came forward as best to turn on or off a light.


Measuring activity means measuring accelerations. With an accelerometer this raw data can be abstracted from reality. You can see in the figure above that there was onlya two axis accelerometer available, but in the final concept there will be athree axis accelerometer. The difference in data will be that when the accelerometer is horizontal (so the gravity acceleration is in the z-axis) there will be less activity measured, because the gravity is no factor anymorethen.

This figure shows the ­­_stdDef 800. The last 800 pieces of data are saved and a mean is extracted from that. The absolute difference between the mean and the last datagives a level of activity. That again is saved and summed up. So no differencein data will lead to less activity.

The activity from each axis is combined into one number. This number is compared to the boundaries. With the unpack each led is controlled so that the first ledwill go on when the first boundary is reached, the first and the second when the second boundary is reached and all of them will go on when the lastboundary is reached.

This code is sufficient for measuring the activity over a short period of time. When looking at the reality the information caregivers want is the activity measuredover an half hour or an hour. Keeping a stream of 1800 * 100 = 180k data is toolong for the computer to process. Also measuring with a bigger interval is nooption because then you would miss important activities. The solution for this is:


Instead of using the _stdDef 800 the raw data from the axis is compared to its previousvalue. The absolute difference is summed up and a metro is added to measure all the activity over the last 30 seconds (image is little bit wrong, 8000 should be 30000). This is a time period the computer can process. Every 30 seconds anumber (certain activity) is generated. This activity then again should be putin a list and streamed over the last 60 numbers (half an hour, 30 min * 2 permin = 60). This is the activity over the last half an hour. 

Postcards Tagging 02


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