Demotech News
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News Wed Nov 24 (2004) -- Fri Oct 21 (2005)
News Sat Oct 18 (2003) -- Wed Jul 07 (2004)
News Thu Jul 31 (2003) -- Sun Oct 12 (2003)
Meeting Hanna |
Fri Jul 11 (2003) |
Tuesday Hanna Hemmink visited Demotech. Picture Hanna: a Dutch woman deeply involved in rural life in Senegal, engaged in projects to improve life in these rural conditions. She speaks the local language, has lived there a long part of her life, and is now travelling between Senegal, France and Holland while organising support for her project.
Hanna's project concentrates on improving gardening in and around her home village Sangalcam. To this end her project aims at getting more water from existing wells in the area. She works mainly with local means while adding better technology to it. She is currently working on a local project in the area of Sangalcam. The aim of which is to spread better methods of accessing water more effectively and rapidly in rural Senegal.
Hanna already came across the idea of the rope pump many years ago. She got instructions from people of the WOT and had these worked out in in a metal workshop in Senegal, where she knows the people well. Her introduction resulted in many good functioning rope pumps. However, she was not satisfied with the idea of the manually driven rope pump and promoted the use of pedal power. Such pedal driven rope pumps are now produced in that workshop. Now she hopes to introduce real progress in pumping water with the use of solar power. She has got the first one (see picture below) working!
It is a great and inspiring event to meet a person who does the things I am involved in myself, who uses the technology I have taken part in creating, and who wants to move further in the same direction as I want Demotech to move in. I hope she will extend her use of Demotech designs, such as that of the WindDrive, with which she is pictured above.
In order to get more people behind her project, yesterday Hanna made the first steps in the setup of her foundation "ATA, support for rural life in West Africa". As a gesture to express hope on future cooperation Demotech donated our DAF-truck to this new ATA foundation. I hope ATA can use this sturdy truck for the same purpose that Demotech originally intended it for: as a Mobile Training Unit
I was fascinated by the photographs Hanna showed me. They show the rope pump integrated in rural life just as it should be. I hope Hanna allows me to use these pictures for a presentation on Demotech's website.
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Deep innovation: long vision, small steps |
Thu Jul 10 (2003) |
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There is plenty progress now with the pulley setup for Senegal. The mockup for the well ring, looking like the one in Senegal, gives inspiration. Rogier and I work on 'welding' the wooden sticks together. Once again the choice for details at the moment of actual making is a different one than what I had in mind only a short time before that. And often the difference is big and consists of real improvement.
It keeps surprising me, that such effective solutions can not be designed beforehand. I really thought I did design an effective solution, but practice offers more, much more. It teaches me what I did overlook and it offers far more opportunities than I could have thought of.
Looking back at the whole process of design for the pulley, I think I was right to be challenged by the worn out locally made pulley, laying useless next to many wells, while for lifting water these pulleys were indispensable. That was four years back in The Gambia
The long vision was:
Use locally available stuff to make pulleys in some sort of local craft combined with local trade.
Prevent the wearing out that now destroys the pulleys.
Produce them in an effective way, easy to learn, easy to accomplish.
This long vision was -in my expectation- somehow realistic, because of the worn out rubber tires laying around. It seemed probable that the properties of rubber as well as its round shape would offer a starting point.
Well, it actually did. It did as well offer stiff resistance to let itself shape in something like a pulley. By taking small steps, some progress was gained. What really helped was the interest of Ives Faye for his Keur Moesse project in Senegal. That gave the urgency that I needed to overcome the difficulties I encountered. One of them was bending the rubber in a V-groove like shape and sewing it with bits of wire. An other big obstacle was the way the spokes had to be made. Both problems could not have been overcome in a design made at the very beginning. Only when some of the other problems had found a likely solution, only then these difficult steps could be taken with some result.
Only when the pulley wheel was introduced in the project in Senegal (Februari this year), only then I got some grip on the problem of mounting the pulley over the well. Again the preliminary ideas of how to solve it with concrete and steel melted away at the moment of having to realize them in practice.
Though now there is plenty of progress and the present construction looks realistic, there still is al long way to go. First it has to prove to be functional, to give a real good ergonomic working position for lifting water with two bags. I know such a system can be very effective compared to other ways of pumping water from deep wells. The final test can only be done in Senegal, may be in August or September.
But a harder nut to crack is to create the reserve strength of the supporting construction. The pulley, its axle and the supporting structure have to be strong enough to lift two people out of a well in case of an accident. Such a situation will someday occur. At that time the pulley may not fail to take that load.
When I set out for the design of the pulley I did not have the slightest idea such a demand would ever be made. But it is also encouraging that this extreme demand can -at the very end- be positively answered.
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An extra function for the pulley support over a well |
Tue Jul 01 (2003) |
It is high time to create a consistent idea for the set up of the supporting construction for the pulley over the well. It is not so easy, as it has to be rural technology, meaning it has to be made with next to no tools andd very rough materials.
We do the research in the garden next to our workshop. We made a mockup pf the size and giving the impression of the upper-structure of a well such as at the site of Keur Mousse in Senegal. Experimenting was done by tying bamboo sticks with rubber strips cut from an inner tire.
Today I worked on an added extra design specification; it should be possible to safely lower and lift a man into and from the well. This puts an extra load on the pulley. But for the construction that supports the pulley over the well, it means it now has to withstand a large force sideways, not only vertical because of the weight of the water. This sideways force is generated when a group of people pull together at the rope away from the well. Such a force is equal to the weight of the person being lifted and should not shift the support itself from the well.
To get some grip on how to get it right, Rogier and I made three full size models with bamboo sticks tied with rubber. Our final model, a tripod, will Thursday be composed out of sticks, cut from the bush around and put together with the use of "Welding Wood".
It was high time as well to put the information on the construction of the pulley and the supporting stand on Internet. That is done today as well.
Old news |
Wed Jun 25 (2003) |
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I cleared about three meter archive. Most of it was old administrational stuff and copies of reports that needed not to be kept. They are back in the paper recycling, giving our office some welcome extra space.
However I also came across many items that I very much liked to see again. One of these items was the front page (sadly only the frontpage!) of a construction manual of the rope pump, such as Valentine Julien and I made, when we still in Ambon after a project on the constructing of wells in Waipia at Ceram/Indonesia. That was back in 1986. Also photographs made in that project of work done on the well cover ring. Pictures from that manual frontpage now help explain how a rope pump can be mounted on the wll cover ring.
Right now old news is news again. The picture shown here was taken in 1976, showing farmers lifting water from a well with a rope and bucket. Jos Besseling at that time was working on the rope pump in Burkina Faso. He also worked on the manufacring of pulleys to ease the watering of cattle. His approach was different from what we try out now on behalf of the project in Senegal.
He used a front wheel hub mounted in a disk of hard wood cut to size on a wood lathe. Much water could be lifted from a well using two rubber bags at each end of the rope running over this pulley. His findings in that experiment are very inspiring: the pulley with dubble bag system lift about as much water as the rope pump. Precondition is a good working position for the person pulling the rope.
A good workng position, that is still lacking for the Senegal project. But not for long! Rogier and I made the first crude version of a support for our version of a pulley. Next week I should be able to report on it with some images.
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Facelift for the Demotech website |
Tue Jun 17 (2003) |
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We put more common sense into our home page. It just grew organically. In the beginning I thought it needed an impressive letterhead kind of name
to begin with. It took some time to find out this was just a wasting the visitor's attention. Then it took more time to find out how to do it better. The answer: just act
functional!
The menu now is reduced to the bare minimum in height, but located at a place where people will look for it. The name Demotech is still there.
Reduced in size, but still making clear this site is Demotech's site and Demotech has something to do with the many pictures and the pump
animation. Not hard to get a general impression in a few seconds.
The width in pixels guaranties it fits well on a 15 inch monitor. The guess is 15 inch monitors is the seize used by our most important clients,
the NGO's in Third World countries. There is no need to scroll sideways. A little scrolling up and down helps.
New, apart from the homepage layout, is "Presentation". Presentation is the database that contains presentations, such as the excursion in pictures in our workshop. More often presentations will be used to create construction
manuals such as the WellCover construction manual .What now is visible is just the very beginning.
Marc van der Kamp works on integrating and linking "Presentation" with the rest of the database.
"Presentation" will be used in three different modes:
For a sketchy presentation of a recent experiment, meant to keep people informed who somehow participate in that experiment.
To show a properly edited version of a construction manual, combining text and illustrations.
To make a slideshow to clarify more complex ideas, such as "What is Demotech about". As Demotech's targets are beyond what can
be considered 'reasonable', indeed such a presentation better should be clear and impressive.
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Storing stuff |
Tue Jun 03 (2003) |
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Suppport by diagonally placed sticks
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All the stuff we gather in our lives need to be stored, often on shelves. Demotech itself has an enormous mass of small and larger things that has to put away, but have to be within easy reach on the other hand. Such as our book keeping and our kitchen stuff.
Though we were in dire need of them, in some cases to make shelves proved difficult;
Our walls were unreliable to attach something to. They were too soft, or too uneven.
To use the floor to stack the shelves on, was unpractical as well. It was not flat, but the real problem: it was not available, as needed for other purposes.
Neither offered the ceiling an easy attachment. The beams for the roof were strong enough, but the space between them did seldom match the lengths of the shelves.
Above conditions also occur in the millions of dwellings in shanty towns, where only the roof beams offer some hold and walls are fully unreliable to fasten anything to. Making this a problem worthwhile to be solved.
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A frame atteched to
the roof beams
now take the load
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The way out was to construct a base structure from the ceiling and go from there. Even then we had a long way to go and experimented over the years to find a method, where shelves could be prepared as modular units, to be interconnected by frames, hanging from this base structure attached at the ceiling.
A problem of stability had to be solved. What hangs down can sway. Shelves with stuff stored on them should not sway. We lined out the spacers between the shelves in a way they all were pulled out of the middle and wanted to sway back, specially when some load was put on the shelves.
For this reason all shelves want to sway back against the wall, press themselves against the wall, causing this hanging construction to remain fixed in one position.
Still there was an instability of the shelves to overcome. The lower shelves had the tendency to turn backward over in conditions of load. Our solution for it did not work very well. (first picture). This solution consisted out of sticks diagonally positioned, guiding the load from the front to the wall. It was a messy set up.
What turns out to works better is to extend the primary frame attached to the ceiling. Now it reaches from one beam to the other, whether these beams run even to the wall or cross wise (lower picture). The trick of the shelves, each swaying back into a stable position, now works well at last.
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Making news |
Thu May 22 (2003) |
Ives Faye will get some well deserved publicity from the Dutch EO-television broadcast company for his garden project in Senegal, where the new well is finished, offering plenty water at 40 meter depth. He phoned me only a few days ago that he would come today to our workshop together with a television crew.
Short notice for me. I could not prepare the well mockup, the full scale model to give people in Keur Mousse in Senegal an idea what we expect to build.
But I just finished in time a new way to make the plastic rope bearing for the pulley wheel axle (see picture). It asks for a lengthwise cut in the end of the frame rod. I expect a blacksmith can get it done when the ends of the frame are made red hot in his furnace. With this setup it is much easier to wind the rope cross wise from the frame over the axle buts to form the bearing. It looks neat and effective.
Ives and his wife told the television people the story of the why and how of their Keur Mousse project. I had liked to focus attention to the pulley wheel, but Ives choose to put the rope pump forward. Together with Ives' and Els' their kids, I explained once again in front of the camera how the rope pump works. In just under ONE minute!
Evaluation of Demotech's presentation on the web |
Sun May 11 (2003) |
The weekend was used to reconsider the presentation of Demotech targets and policies with the means available in a website. The question of what Demotech is about, stood central. Currently the menu-item 'About us' links to text, but this text may not clarify in a visitor's mind the exact direction of Demotech's policies. How could this be done better?
Richard Zuidhof, Marc van der Kamp and Rejo Zenger have the experience in web-design to offer alternatives. It was my task to relate these alternatives to the present setup of our website.
The usual way in which presentations are made to an audience with a projector and images using MS Powerpoint seemed an effective as well as attractive option. It could combine short bits of text that relate (and are hyper linked) to a cluster of information. Such text could be displayed with a related picture as background. Text items with background could then be presented as a series of slides. How could this idea come together with other demand for a presentation of text related to images?
Two more text-picture related items need attention. One being the downloadable manual of a design. Which is what future users need. The second is the description of prototype development process. This is essential for making use of the feedback from others through the website. People collaborating with Demotech do not need a polished presentation, just a rough and sketchy presentation will do.
Rejo and I feel attracted to the simple but clear set up for a construction manual found on Internet. Marc promised to look into the possibility of programming the above three options for the Demotech website.
Search and what we are searching for |
Mon Apr 28 (2003) |
Should this website have a glossy finish before it is published? People accustomed to regular product promotion will say "yes, it irritates to look at unfinished and untidy stuff. There is no compagny who dares to risk that".
This website for sure, does not have a glossy finish and I doubt if it ever will have a finish at all. I like to take the risk because:
- The basic innovation, that we pursue, cannot give a final result for a long time to come. It is impossible to program its progress with any certainty.
- Anything left unfinished is an invitation to others to join development. What we publish, we publish as a contribution to Open Source interaction.
- Time is better invested in continuation of design instead of in an in-between stop.
Today I had a conversation on this subject with Dina Septiani (see picture), a student at the University InHolland in Diemen. She came over to our workshop for an interview about our website.
It struck me how much intellectual capacity is available in the environment of a school as this one, also remembering our interaction with its students Ayunda, Zhu, Farah and Lillian, half a year ago.
Over the years, interaction with students has always been very inspiring. They said it was inspiring for them, we felt the issues put forward by us, really mattered for them and could count on support in some way later on. Could it be that there are better ways for interaction between students and Demotech?
Last Saturday Rejo and I discussed with four students of the faculty of Industrial Design of the Delft Technical University how to shape an "inspiring environment on design for sustainability". At stake is the use of our workshop in Dieren. How to link our "inspiring environment" with the wish of students to have some reference from a radical design approach?
Some ideas were put forward, we will continue to work on them.
Today a big step forward was made with our website. As our website will soon contain more than five Megabyte of information, it will be a good thing to be able to find information by a search query. Marc van der Kamp has now created this potential. From now on it is possible to fill in a key-word in a search window and get the immediate result neatly sorted out by our database.
Marc is working on extending this search capacity. Soon it will be possible to sort information on categories of design, progress made so far, design targets and many other issues.
Forking in ventilating the chimney-less wood stove |
Fri Apr 25 (2003) |
Forking is the expression for a split in approach, a new way taken up next to the research that goes along according to a previous plan.
Bram de Vries, one of the people I recently met through the contact with LHUMP thought different about a method to create the draft of air through the stove.
Demotech proposed the use of a Stirling engine. Such a machine could have a very low efficiency, as heat was plenty available in a stove, while the energy needed to drive the ventilator was but a little.
However Bram asked himself the question how to reach the same effect with even less moving parts. Today he came over to our workshop to discuss and demonstrate his ideas.
He started experimenting with a tin can functioning as a vessel to heat up air. Over this vessel a rubber membrane is attached with an air valve in the middle. This valve should switch at reaching the top and the bottom of its stroke, thus creating a draft by sucking air in and pushing air out.
Bram realizes his forking concentrates on a mechanical train of thoughts. Next step is to discuss it with people who can make a proper calculation, as the expansion of air by heat can be properly calculated. To inspire these people he plans to make in his kitchen at home a new set up, clarifying his idea better. Such a contraption could even shown a first sign of life!
News Wed Apr 23 (2003) -- Fri Feb 21 (2003)
News Sun Jan 19 (2003) -- Wed Nov 13 (2002)
News Tue Nov 12 (2002) -- Fri Sep 20 (2002)
News Mon Sep 16 (2002) -- Thu Aug 08 (2002)
News Mon Jul 01 (2002)
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