Motor master
One of first persons that everyone serious about Lego Technic gets to know is Philo. That’s because we need to know the performance of Lego motors to use them well, and there is no better specification on that than the one Philo created. His work has been crucial for many competitions, like for instance Lego Truck Trial. Moreover, Philo is also an outstanding builder, with many impressive creations and ideas both on the Technic and Mindstorms field. Personally, I have been using his specification constantly for more or less three years, so it’s just about the time to talk to him 
Klocki - Hello Philippe. I’m pretty sure that many of our readers are familiar with you and your work, but let’s start with a little introduction anyway. Could you please say a few words about you, your creations, and how did you started to build with Lego bricks?
Philo - I am a 52 years old electronics engineer, living near paris in france. when i was young, my lego bricks collection was small (it included some pre-abs era bricks!), but i played a lot with them, before my hobbies shifted to chemistry and electronics. i was about thirty when i discovered lego again: the newly launched Technic sets appealed to the engineer in me! As I was already fascinated by robotics, I created some little electronics modules to automate my creations. These modules, based on a few relays, transistors and switches, were assembled on top of LEGO plates for easy integration to models. When properly interconnected, they were able to control a vehicle going around obstacles detected by bumpers. At the end of this period, I bought the Control Center set. Though the models included were quite good, I was disappointed by the imprecise controller lacking sensors feedback. It was only several years later, end of 1999, that I got interested again when the Robotics Invention System was launched in France. I bought this set as a birthday gift for one of my daughter… and soon played with it much more than she did!
- You are, among others, a prominent builder. I have noticed that although you have published a limited number of constructions over a period of several years, all of them appear to be extremely complex and well-considered. Does it mean that you take a lot of time to work on every single of your constructions, or perhaps there are things that you’ve built but never published?
- I am definitely a slow builder - and a slow writer, as exemplified by the time it took me to answer this interview! But indeed there are many things I never documented; several GBC modules, sumo robots built for FreeLUG competitions… Of course I have little motivation to write a paper on creations that I consider to be a failure. For example the tripod shuffler I built for an internal competition of MCP2 forum. While the basic moves worked as intended, it was rather fiddly about ground friction, and did not achieve its goal of navigating through a simple maze.
And also, some of my creation have a long gestation time because of their complexity. For my latest MOC, the 3D scanner, mechanical construction was fast, only a few hours. But getting the program to work was not simple. I had to learn the basis of Lua (the language I choose for this project), find my own bugs… and also a few in pbLua that was still in beta state. Fortunately, Ralph Hempel, pbLua author, was very helpful! After that, I had to climb the rather steep learning curve of Meshlab, the 3D reconstruction software I used to assemble the scanning results. Add to that the time needed to motivate myself enough to do the write-up, and you get a 6 months period between the first brick assembly and the publication on my website!
- Another one of your activities is creating excellent quality LDraw models of certain Lego parts - expecially the latest Power Functions elements. What can you tell us about it? How is such a model created, I guess you need to take extremely precise measurements of it?
- I discovered LDraw a few years ago when I started building my own mechanism and needed to document them. LeoCAD, the LDraw editor I found at that time, is still - by far - my favorite virtual LEGO tool. But I soon faced a problem: many parts I needed were not yet modelled! Fortunately the LDraw Parts Tracker was created and through it I got in touch with LDraw parts author community. At that time, part authoring seemed overwhelming to me, and for years my involvement was limited to a few simple parts creations and reviews. About two years ago, one prominent author stopped producing parts. By necessity I started modelling seriously, and became more and more fluent. I also created several tools to create warped surfaces or calculate intersections between them. With these tools I am now able to create the complex shapes more and more frequent in modern LEGO parts (think “Bionicle”!). These achievemnets got me recognition from the LDraw community: I was very pleased and proud of receiving the 2008 James Jessiman Memorial Award.
About measurement, of course some are needed, but many dimensions are fixed and known because of LEGO geometry. No need to measure brick length, stud diameter or Technic holes spacing! The first step of modelling is to place all these anchor elements, and then you just have to “fill the gaps”!
- Other than being a builder and a modeler, you are also a co-author of the book on the Lego Mindstorms NXT system, the “Extreme NXT”. What was the reason to write and publish such a book? What level of Lego builders should be interested in it, and what can a reader except from it? Are you perhaps thinking of another book?
- While software hacking of Mindstorms products is fairly common, the hardware counterpart has only a few proponents. So Mike Gasperi was able to convince me that there was a need for such a book - and to co-author it. It was a timely decision, since LEGO made hardware tinkering on the NXT easier than on RCX, by means of design choices (separate power on sensor ports, I2C support) and documentation (publication of NXT and sensors schematics). This book will probably appeal more to the robotics enthusiast who wants to extract more juice from his NXT kit than to the pure LEGO builder. The purpose of this book is also to demistify electronics that is much more simple to grasp than it appears. The NXT, with the numerous protections built in its I/O ports, is an excellent test bed for that!!!
We are seriously considering writing an updated second edition of “Extreme NXT”, but except from that chances are very low I ever write another book. I am definitely not good at that exercise. Fortunately the talents of Mike made this book hit the shelves!
- One of the greatest, most useful things you have done for the AFOLs society are the detailed specifications on the performance of Lego motors and tires. You have run a number of very complex tests, many of them including sophisticated instruments. What has inspired you to all this effort? Are there some additional tests that you would like to do in future?
- One of the first events we organized after FreeLUG birth was a sumo robots competition. Of course the engineer in me wanted to have factual data to make the right design choices! That’s how it all started. I discovered a lot in the process, not only on motors themselves, but also on all protections and current limitations built into battery packs and into the RCX. The measurement process for motors is now well defined and provides reasonably accurate data, so I can easily add new LEGO motors to the list.
On the other hand, tire traction measurements depend a lot on the surface used for testing, so the figures derived from experiments are less interesting. So I don’t intend to add new tires to the list.
Some time after I published these pages, I proudly discovered that they were even used at LEGO! When a customer asked them for motors characteristics, LEGO people could not reveal their internal data, but it was no problem to indicate my pages as a source of information!
- I know that you have been in touch with Lego for some time - for instance, you have tested early versions of the PF Medium and PF XL motors in your tower crane. What can you tell us about it, how did it start?
- My first official contact with the LEGO company was for beta-testing the new NXT. LEGO launched the “Developers Program”, and I was lucky enough to be among the 100 people selected within about 10000 applicants! It was a very exciting opportunity, only compounded by confidentiality issues: you sometimes feel bad when you know things but you can’t share this knowledge with friends! Since then I am a member of “MINDSTORMS Community Partners”, a group of about 25 fans all over the world. This year is especially noteworthy, with the upcoming launch of NXT 2.0 and also because of the 10th Anniversary of MINDSTORMS. We were invited in Billund for the celebrations, and were very happy to meet each others and be more than names in e-mail headers!
The Power Functions collaboration started when LEGO Ambassadors were asked for potential AFOLs testers with some electronics knowledge, and a friend proposed my name. I guess I was selected also because of my motors comparison page… When I signed the NDA (non-disclosure agreement), I knew nothing of the project, but since in was about new LEGO stuff, it was obviously something interesting! The group had many discussions about this new system , and the consequences for the AFOL world of dropping the old 9V connector. We tried to convince LEGO people to keep some compatibility between both systems, and it seems we succeeded since the PF extension cable is equipped at one end with a mixed 9V/PF connector. Later we received early prototypes of PF elements, from which I built my tower crane, and we were invited to a building workshop in Billund. We had a wonderful week there, building with the new system to evaluate its potential and discussing its future extensions, for example the PF LEDs and the linear actuators that appeared in 2008.
- What does your relation with the community looks like? Do you keep following the work of some builders, or watching all the news and events within the community? Are there perhaps some builders that inspire you, or that contact you to tell you that you have inspired them?
- I do follow several news blogs, either generalists such as Brother Bricks and Klocki, or specialized like The NXT Step or TechnicBRICKs. Lugnet was a great place to keep in touch with the community, unfortunately it is now much less active because of the numerous thematic forums here and there. I regret this situation because while I am focused mainly on Technic and MINDSTORMS, it was nice to have at a glance a panorama of the complete LEGO fan planet.
- It appears that throughout your ‘building career’ you have from time to time worked together with other builders - e.g. with Hiroki Shirakawa. What was it like, and do you like the idea of working together with somebody else?
- I tend to be a solitary, something perhaps inherited from beeing an only child. So my collaborations with other people are kind of “losely coopled”, mutual inspiration, building on fundations laid by others rather than true cooperation. For example I borrowed Bob Kojima’s rolling ball clock to build a more precise RCX controlled version, and adopted Jetro de Chateau light barrier design to improve reliability of my Spybotics based GBC shuttle module… (conversely, Jetro was inspired by my design to build the mechanical design of his module!).
I once had the opportunity to meet Hiroki who stopped over at Paris while coming home from a trip to Africa. We had great fun exchanging ideas about the little walkers he devised!
- As you witness the development of the Lego bricks in general, the new generations of parts replacing the older ones, what are your general impressions? Do you see a lot of space for future Lego development? Are there perhaps some parts that don’t exist today, and you would like to
see them around in future? I, for instance, still hope to eventually see Lego making helical gears.
- I keep confident in LEGO commitment to release new interesting parts! After all this is the best way to protect their models: they can’t be built if you don’t have the right new part! Overall I am really pleased with recent additions to LEGO parts folder, from the powerful Power Functions motors and linear actuators, to the new plat and cylindrical panels, easier to use than convoluted previous versions. Studless Technic construction (a revolution in its time), while slick and compact, sometimes suffered from lack of stiffness issues. The new studless frames should improve that… Of course I have a few dream part, such as a Power Functions replacement for the micro motor, or a pneumatic valve to ease robotics control of pneumatic pistons. And some odd length bricks and plate would be great to ease studded/studless combinations! As for helical gears, I doubt they will ever exist: molding them economically would require a technological breakthrough!
- Is there something you are working on right now? Or perhaps you can reveal to us some of your plans for future?
- I am not a long time planner, ideas come and go and only a few ones are turned into ABS… One of my latest creations is a coloured balls sorter using only NXT-2 parts. Its mechanical design is modelled after industrial pick and place machines. You should see more about this robot in the near future! My latest LEGO related project is yet another LDraw tool to ease modelling of 3D printed patterns.
- Thank you for your time, and for all you’ve done for us.
Thanks for your patience, waiting for this long overdue interview… And congratulations to the many outstanding Polish builders I discovered through Klocki!
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