Exploratory sketching

In this sketch you can see the vanishing point of the tape roll holder is in front of the object which is very strange looking.

Also the alarm clock has the problem with the vanishing point on the wrong side of the sketch.

These 2 sketches are made before class as well as the 4 sketches below, the printer looks good on the bottom side but at the top side something strange happens which is caused by the left upper corner which goes to much to the right which causes the printer top is not in the center of the printer but slightly of set to the right. This could be solved by making the curve the same (but reversed) as the curve on the right side.

This sketch was to communicate a scene. I used numbers to indicate in which order the sketch needs to be read. in this case first the watch gathers data from the user and decides if the user needs to be activated (in this example the user is sitting on a chair which vibrates) and the overall progress of the users is visualized on a very wide screen on the wall on which they all conquer a common goal.

I already sketched 2 1/2 hours in the park Wednesday, I studied different perspectives of the photo camera and some other objects given during the assignment. I will post these sketches as soon as I finish the other other hours(probably Tuesday). 

A step closer to autonomous sailing

At this moment i'm a step closer to the semi autonomous sailing vessel.
I completed the code to adjust the rudder gradually depending on how big the turn needs to be.
This means that when the boat has to correct his course 1 or 2 degrees the rudder will only make a very small movement and when for example the course is changed from 90 degrees to 120 degrees there will be a bigger rudder deflection.
the incoming data is based on a compass from sparkfun (LSM303) which is a tilt compensated compass which is very valuable for a sailing vessel, it doesn't check the information with the GPS module at this moment and I doubt if I will manage to implement the GPS module.

The next step for me is to implement the wind sensor in the code and adjust the main sail according to the data from the wind sensor. In this way the main sail will always adjust its settings accordingly to the wind and thus have always the optimum position.

The compass module connected to the arduino. 

on this picture connected to the computer to read the serial 

communication and in this way check the program.

Deaf Presentation

Last thursday we were at DEAF festival, where we presented our project and met Cesar Harada and some other members of Protei and other interested people. here you see some photo's of the meetings which took place. later I will also post the photo's of other interesting parts on the deaf festival.

As a very cool present, I got an actual oil boom to test with.

Also, we are nearing the end of our semester and are therefore presenting our work at our final exhibition at TU/e. We will be presenting our work on Thursday June 7th, form 9.30 to 11.30 and on Friday june 8th from 13.30 to 15.30 in the Next Nature Theme (that is in the purple space on the 4th floor of the main building of TU Eindhoven) you are very welcome to come visit us and see our work.

update

at this moment i'm working on the report and on the assignments but I do not have enough time to also write on the blog.

scenario

My first design concept was about; how users could design and build there boat themselves and then put those boats into the sea and control them from there own homes. After working on this project I found out that many of those boats which are build aren't good qualitative build boats. By keeping in mind that the garbage spills in the ocean keep growing (source: http://www.wlsam.com/Article.asp?id=2452508&spid=) it can be considered not so smart to let everybody build there boat and put them at sea without a quality check. 

At this moment however we aren't ready to build autonomous boats and let them sail the oceans to clean up oil. this research process is in a too early stage for this. I build this boat not to facilitate the mechanical/physical innovation for protei, such as the shape-shifting hull, but more to explore the innovation of the intelligence and control of the boat.  When more of these boats are build also inter-boat cooperation can be researched.

So what I facilitate is a platform for competition between different protei developers which are developing new versions of this boat at home and improve the design and test it themselves. The outcomes of all these individual developments are shared in the community and in this ongoing competition all users will build upon the previous design.

In my final report I will include an extensive how to build chapter to reproduce this boat and build upon the things I've designed

thoughts about protei

At this moment Protei is in his research phase, a change in culture caused that this research isn't done in the conventional way but distributed over a large open source community. I'm one of the many people working on protei and even I work in a small community with my fellow wild robots project members.

My research project focuses on the sailing drone, which is part of the bigger system, with a mother ship which can collect the oil-absorbent tails when they are saturated, flying drones to spot where the oil is etc.

In this bottom up research process I build one sailing drone which is the basis for researching autonomous behavior the boat can fully adjust his actuators and can sense where it is, in which direction it is heading and where the wind is coming from, also the speed of the boat and how much leeway the boat has (+ other data derived from gps). The complex system I created in this way with a bottom-up approach can now be extended. The Boat I build cannot be send to sea and clean up oil already, but can show the capabilities. Also it shows that home build boats (see also the project of Martijn and Stijn) which are made by children aren't seaworthy. But can increase the knowledge about sailing drones. Therefore this distributed research method is very powerful in creating knowledge and building upon the existing knowledge already created by the community, which in the end enables protei to build and manufacture hundreds of highly efficient complete autonomous sailing drones which can clean up oil spills and at the same time collect data at sea.

Because this is a research project, I will also work on the collective paper of protei to publish my findings during this project and pass on my knowledge to the next group working on this.

electro permanent magnets -update

Today, I researched the possibilities to lock a servo with electro- permanent magnets. This solution still seems possible, but isn't recently used for this application. Therefore I cannot guarantee at this moment that this technique will work. However I contacted a manufacturer of electro and permanent magnets about the possibilities and he will contact me soon. At the electrical engineering department I spoke with around 10 different professors in different fields of expertise and all of them didn't really know how to apply this on a servo motor. This was a little disappointing for me, and the best thing was to use a stepper-motor with permanent magnets inside. After looking into this I figured out that short cutting the wires of a stepper motor increases the friction inside the stepper motor, but still this force isn't strong enough to maintain course at sea.

Hopefully the manufacturer of these products can explain more about this technique so I can design the new servo with with zero static power consumption.

I also found another application of electro permanent magnets which are the cubelets (http://www.hizook.com/blog/2010/12/07/electropermanent-magnets-programmable-magnets-zero-static-power-consumption-enable-s)

This website explains how you can build a steppe rmotor with the use of electro permanent magnets so this application has the lock function within the motor itself instead of my version with an external lock mechanism.
Essentially this combined my research into stepper motors and the electro permanent magnets. Unfortunatly for me it is already patent pending....

Quote:

Electropermanent Magnet Stepper Motors:

One very interesting outcome of Ara's thesis was the development of (patent pending) EP magnet stepper motors.  This tiny "wobble" stepper motor uses EP magnets in place of traditional stator windings (electromagnets).

  

By switching the state of nearby EP magnets, the motor will step through various (rotational) configurations.   

Owing to the unique properties of EP magnets, this type of stepper motor offers some interesting benefits.

1. At low RPM (very little on-off switching), EP magnet motors have higher efficiency compared to electromagnetic motors.

1. At zero RPM ("stall"), EP magnet motors still outputs constant force / torque.  In electromagnetic motors, stall conditions result in massive power consumption -- this is a major problem for motor startup.

unquote
source:http://www.hizook.com/blog/2010/12/07/electropermanent-magnets-programmable-magnets-zero-static-power-consumption-enable-
http://www.hizook.com/files/users/3/Electropermanent_Magnets_Knaian.pdf

Windsensor and compass

The recently developed wind direction sensor is of course a nice feature for a sailing vessel but it isn't complete without a compass. This week I will combine a digital tilt compensated compass with the wind direction sensor. in this way it is possible to adjust the sails according to the wind and keep a certain heading according to the digital compass. In this way we will have an semi-autonomous sailing vessel which will automatically keep his heading and will adjust his sails according to the wind.

hope to update you at the end of this week about the progress regarding this matter.

electro permanent - servo

During this semester I used Servo motors as actuators to for the sailing drone. These servo motors require constant power when a force is applied on the rudder or sail. In other words they just require constant power because the wind always applies a force on the sail as well as the water applies a force on the rudder. Therefore I started looking for other ways to steer and adjust the sail. Unfortunately there are not really power efficient actuators on the market.

But recently I saw an article about "kleefklimmen" (http://www.schuttevaer.nl/nieuws/actueel/nid12488-europort-kleefklimmen-op-europort-2009.html) a technique which uses electropermanent magnets to climb on any steel structure (or any magnetisable material) The main advantages of this system are no power consumption while the magnet is on, which is much saver in the application of climbing. But this technique of electro permanent magnets can also be used to lock the sail actuator and rudder in position which cause them to use absolutely no power while they are locked in this position. Because the sailing drone will sail large distances in the same direction the and sail settings don't need to be adjusted continuously which can save a lot of energy.

The sailing drones will be autonomous and thus harvest their own energy with solar cells or in any other way. But the fact is there is a limited amount of energy available for the sailing vessel at open sea. Therefore this system can save a lot of energy, compared with normal servo's which require constant power.

For now I will make an appointment with Henk Huisman an expert on electro permanent magnets which I came in contact with through Bas Gravendeel the inventor of "kleefklimmen". in the next post I hope to give more information about the strength and power consumption of the system as a total.


For those with a bit of physics background, these B-H curves tell the story

presentations next nature

During this Semester we present our work 2 times. Last Friday was the second time we presented our work so far for the next nature theme.
For this presentation I wanted to show what I've achieved in the past semester and my final steps to end this semester.
In the video below you can see my presentation.

Wind sensor

To build an autonomous sailing vessel, a wind direction sensor is necessarily for the boat to function. Unfortunately there are no off the shell wind direction sensors which are cheap. On the internet there are amazing prices starting from $150 till thousands of dollars.

The target for me was to build a wind direction sensor for less than $15 dollars (10% of the lowest internet price).

Finding the good electronics took some time, potmeters aren't able to rotate continously so the best solution was to use a rotary encoder. There are 2 types of absolute rotary encoders; optical and mechanical.

In this case to optical rotary encoder is used works with gray code and works in the following way:
the optical encoder's disc is made of glass or plastic with transparent and opaque areas. A light source and photo detector array reads the optical pattern that results from the disc's position at any one time.
This code can be read by a controlling device, such as a microprocessor or microcontroller to determine the angle of the shaft. (source: wikipedia.org)

the other materials I choose to work with are perspex because in this way it is easy to see how the wind direction sensor is build, but essentially can be made out of every material at hand. 

The most important part is to protect the rotary encoder from the force of the wind and only let the rotational force work on the rotary encoder. Therefore I build a shaft around the rotary encoder which will prevent the wind banner to bent the electronic parts.

The total costs of all the materials are:
COM-09117 rotary encoder from sparkfun                               €2.24
2 perspex tubes diameter 21*16 and 15*11                                 €2,00

Vivak sheet 300*300 mm*1                                                              €1.69

___________________________________________________

total                                                                                                               €5.93

presentation next nature last week

a few seconds are missing between part 1 and 2. personally i'm not completely happy with my presentation. and especially afterwards I wanted that I could elaborate more on the concept

cross coach meetings

During this semester next nature changed the way we get feedback during a semester.
Twice during the semester we present our work in a 3 minute presentation per person and three times during the semester we would have cross coach meetings were other coaches would give feedback on the work of all students.

Unfortunately the presentation session didn't worked for me to get feedback. Even though I had 3 specific questions/ areas I wanted feedback on, the audience didn't respond to my request. This feeling was shared among other students and also the cross coach meetings were not succesful because only my own coach showed up during the first and second meeting. So even then I couldn't get feedback from another perspective.

After a meeting with Koert van Mensvoort (team champ of next nature) we decided it was to early to draw conclusions based on a half semester, but I was free to arrange anything I liked. So at the start of the semester I just talked with several other coaches as well as students to get feedback on my process.

I organised my own cross-coach session with 2 coaches and the protei/wild robots group. During this meeting I was able to receive quality feedback and below you can find (a long!) video of 2/3 of the meeting (last movie file is corrupted).

movie on update when youtube is ready

exploratory sketching

lesson 2 click on the picture to enlarge

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User interface

After the expert meetings it became clear which parameters should be used to control the boat.
The parameters which need to be definitly given by the user are the heading or location the boat has to go to.

Further more I would like to have more options for the user, in the end, the user has build his boat and put a lot of time in it, therefore I want to give the user the option to control more parameters of the boat.
This is the reason I conducted a small user test with 9 users.

The prototype consisted of several layers which can be turned individually, the layers are:
- the boat
- compass
- sail
- wind direction

The goal of the user test was to find out how people want to navigate their boat and how they can adjust the sail.

In the user test the wind direction was given and also a desired heading was given to the user.
8 out of 9 users preferred to turn the boat to the right heading and one of the users turned the compass to make the front of the boat heading into the right direction.

adjusting the sail was found really easy for all users. However the user test was conducted with a physical prototype and without text explaining the functions. In the end design the user interface will be digital, so I cannot draw conclusions out of this test regarding the final design but this helped designing the next digital design.