I’ve never done anything bot-related and just couldn’t let it stay that way. A couple of friends and I (Hi there Miguel and Gonzalo!) have put together this simple bot and will be playing with it to discover the wonders of the Wiimote shortly.

It uses a Skypic board as brains and a Sky293 board for power, both of which are free hardware licensed under Creative Commons. Besides that it has some cheap sensors, the simplest skeleton ever, a couple of Futaba servos and a Wiimote (yet to be incorporated) as inexpensive do_it_all sensor. It’s not that a Wii Remote is cheap. Compare what it has to offer (accelerometer, optical sensor, Bluetooth connectivity) to the price of any single raw component from that list and you’ve got yourself the best deal ever!! And yes… if you own a Wii you can play with it too as a bonus. Thanks to Andres Prieto-Moreno (Hi, Teach!) for pointing out the possibilities of this little wonder.

Here… take a look.

Precisely one week after releasing the long awaited 0.6 version of this web server, Cherokee 0.6.1 has been released minutes ago. As I’ve said once and again, the project has been gaining momentum and here you have the download link to prove it.

It is mostly a maintenance release since most of the development efforts are being put towards the future release of version 0.7 with a lot of goodies. I’ll be writing about that when the times comes. For now the list of changes in 0.6.1 includes support for “Personal Web” -a missing feature in this release that was requested for the administrative interface-, a fix for a bug introduced in handler dirlist right before the previous release, and some other minor bugs in documentation, compilation and cherokee-admin.

As before, you’ll have more information at Alvaro’s site and the official Cherokee Project’s website. We’ll be waiting for your input. Happy hacking!

If you’ve made it this far, you are already half way there. This step is the most time consuming of all, so if you make it through the end you are as good as finished ;)

This binding technique will be sewing through the fold, where the signatures of the book are folded and stitched through the fold. Then the signatures are sewn and glued together at the spine to form a text block. The final result should be as durable as that of a hardbound book, and you should be able to open the book completely flat, at least until you apply glue to the spine. Afterwards it wont stay flat open by its own weight. I always glue the spines (Step 5 of this howto) because the text block of a sewn through the fold book is not very secure and some signatures could come loose over time, especially when you make as little as three stitching rows.

First I’ll show a sketch of the steps to be taken. Don’t worry if you don’t understand it yet (I know I wouldn’t: drawing was never my forte) . Hopefully with some explanations and more photographs everything will be crystal clear. Click on the images to show a bigger version. You’ll be needing the extra detail.

Sketch number one shows what you should do with the thread to sew the first two booklets. Here the thread is represented as a black line. The upper half would be the part that runs through the inner side of one of the booklets. The bottom half would be the part running through the inner side of the other booklet. The little green squares indicate the points of entry, the holes on the fold of each booklet, used to get the thread from the inner to the outer side of a booklet and viceversa.

This has nothing to do with computers, but as a Hard-Scifi lover I had to say something about it. I’ve just read that Arthur C. Clarke passed away today at the age of 90.

If you’ve read him (who hasn’t?) you’ll know why this saddens me. If not, here is some information about him and his legacy in case you care.

Here are Clarke’s three laws, probably his most famous quotations:

1. “When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.”
2. “The only way of discovering the limits of the possible is to venture a little way past them into the impossible.”
3. “Any sufficiently advanced technology is indistinguishable from magic.”

A heartfelt goodbye to you, Sir. You will be missed.

As I anticipated some weeks ago, Cherokee 0.6.0 has finally been released. It was a couple of days ago but it caught me away and with no Internet access until now.

Anyway, the trunk was branched on March 6th and after some exhaustive testing and a little polishing here and there … here it is!!!

You should take a look at Alvaro’s site and at the official Cherokee Project’s website. Suffice it to say a lot of work has been put into the new release, and the effort has been well invested. Work will resume shortly to improve an already impressive web server, and as advancements are made towards 0.7 a lot of new features will be added. A fast look at the TODO file will give you an idea of what is yet to come: a bunch of new handlers and modules (WSGI, AJPv13, WebDAV, mod_evasive, upload progress module), generic caching, new header entry, AIO based fdpoll, memcached support, chunked encoding, Dtrace hooks, better language support…

As I said previously, stay tuned. You’ll be able to expect a lot from this project in the near future. That is a given ;)

UPDATE: I forgot to mention the most important thing. Here is the original announcement of the release at the official mailing list.

Before we start sewing everything together, we’re going to need several holes in each booklet to pass the thread through the folds. Instead of sewing directly and piercing each one on the fly with the needle -which, by the way, is hard unless you’re from planet Krypton-, we’re going to prepare each booklet beforehand so that we end up with every sewing point properly marked on every single one of the folds.

You can devise whatever method you come up with, but I think the easiest way to do these holes is making a pile of paper, clamping it and using a knife to cut through until you reach the center of the folds. These are the tools of the trade: a couple of clamps, some rubber bands and a pair of strips of whatever material you find that can be used to hold the paper firmly. In my case I use two metal pieces that were left over from one of the shelves I have in my junk room.

You could build some kind of wooden structure to do the same thing that would be more handy, but this works for me. At least for now.

Not much to say here.

Once you’ve reached this step you should already have everything printed in a pile of 5-page subgroups correctly arranged for folding. You only need to be careful when selecting the pages that should go in each booklet.

I do the folding manually. Just take the pages, align them properly so that none shows over the others and fold them carefully. You’ll need the best possible alignment you can get since the final look of the book depends on it. I usually take the group and have the opposing shorter sides of the sheets make contact before applying any pressure. If you’ve ever done Origami you’ll know that otherwise you’ll end up with misaligned borders.

It has no complication at all, but you have to be extremely careful each time you fold a booklet or the sides of your book will end up being irregular. My folding is never perfect, but it gets close. Anyway the side opposing the spine of the book will inevitably have an irregular aspect since the innermost pages of a booklet will protrude over those at the outer part. Don’t worry about these triangle-like alignments. We’ll take care of them when we get to the trimming part. For now you have to make sure the lower and upper sides of your book are as aligned as possible.

This involves the process of arranging the pages into several booklets and printing them. This might seem stupid, but printing a book is sometimes trivial and sometimes a lot trickier than it looks. You need to print 2 pages in each side of the sheet, and arrange them in a way that results in properly ordered page-numbers once you fold the booklet. I normally work with 5 pages per booklet. More pages is too much once you fold, and less is simply too little. The sewing process is the most time consuming and the more booklets you end up with, the more sewing you’ll have to do.

Typically you’ll be working with a PDF or a PostScript file. I will not discuss Windows programs to print booklets because I don’t use any. I’ve heard of a pseudo-printer driver called FinePrint that manages precisely the booklet printing process, but I haven’t used it and it’s not free, so if you are not willing to use the Linux/*nix programs mentioned bellow you should do some investigation on your own.

Some of the commands discussed here can manage only PDF or PS file, but not both. The ones for PDF are usually front ends for the pdfLatex suite. In any case, you can allways convert from PS to PDF and from PDF to PS, so this shouldn’t be a problem. Be advised though: some conversions from one format to the other can involve a sever loss in legibility, so if there’s a command available for your specific filetype you should stick with that. Another useful thing to have into account is that you can always obtain a PDF file of anything. If you are using Cups you’ve got a really nice pseudo-printer to make PDFs out of anything, so use it!

The margins

I you are using A4 paper-size you are going to end up with an A5-sized book. That is 148 mm × 210 mm, which is fine for a paperback book but you should be careful with the margins in the PDF. Too much wasted space will result in extremely small font-sizes, and even with a perfect eyesight reading such a book can be tiresome.

If your PDF wastes too much space you should trim the pages before you print them. There’s a tool included in pdfjam called pdfjoin. Besides joining pages it can do the trimming part. There’s also a command called pdftrim, but it takes a lot longer to run. I think the reason is that it does some actual resizing.

Normally the margins you should trim will vary and you’ll have to find them out by trial and error. I usually make a smaller PDF to make each test faster. I use pdfnup for this. For example, to make a subset called oud.pdf from a source called in.pdf with pages 40 to 50, I would use:

pdfnup in.pdf --nup 1x1 --pages 40-50 --outfile out.pdf

This isn’t going to be a technical post for once. Besides computers I do have more mundane hobbies you know. A couple of years back I started bookbinding as a remedy for a particularly stressful month. Manual tasks always seem to have a relaxing effect on me, so it seemed as good choice as any.

Eventually I’ll end up buying an eBook-reader and I guess that will be the end of my bookbinding hobby, but for the time being printing the good books doesn’t seem as a bad choice. I haven’t found a machine that suits my needs and is affordable yet. I recently considered buying the Sony PRS-505, but people on the net are not happy with the zooming options for PDF files. Excellent PDF support is a must, so I’ll just wait for better gadgets to come out.

As I was saying, I had recently downloaded an excellent book in PDF format, Dive into Python by Mark Pilgrim, so it was a good opportunity to get into this bookbinding thing. The book, by the way, is published under the FDL so verbatim copying is allowed. Take a look at the sites if you want to know more about the book. It’s around 300 pages and I really liked the no-nonsense, cut to the chase style. Totally recommended.

Since I like that style so much, let’s cut to the chase. Enough blabbing. The process is totally amateurish, of course, and far from perfect. But after some trial and error and several refinements over time, I believe the final result is quite satisfactory.