This time TILTO appeared via Skype at CN23.
It's becaming famous!
Sep 8, 2011
Jun 30, 2011
Blogs
Since publication, on June 13, 2011, the TILTO's video has been reproduced thousands of times and posted in the most infamous tech blogs all around the planet, in english, spanish, polish, swedish, and who knows what else!
Jun 28, 2011
Very First Real Test
Finally, on Sunday June 12, 2011, the Tilto had its first street unexpectedlysurprisingly good, that after so much effort gave me lots of happiness.
This was only the first test of Tilto and there is still too much to improve, but the idea I thought over a year ago is now working.
Mounting the Beast
When the power drivers were tested ("almost" without producing magic smoke during the tests), I went to buy the hardware.
I worked a little in the workshop of my friend Nicolás and a little more in my apartment, and before long I built a simple structure and started the first Tilto's tests:
At this point I faced the most difficult problem: The electric motors (donated by my new friend Gustavo) are previously owned and a little worn, and have too much backlash in the gears of the gear boxes. This produces a dead zone where the system has no control and provokes strong shocks that destabilize the entire unit.
I spent an entire week thinking and testing mechanical solutions, until one morning I woke up with a simple software based solution.
It worked pretty well, and I finally mounted the Tilto beast!
Power Drivers
Happy with the performance of the "brain" I went to the design and construction of the motor driver modules.
The design is made from scratch, using components that could be available in my city (Buenos Aires , Argentina
The result were two switching circuits, in two homemade boards full of MOSFET power transistors, capable of handling nearly 10 times the current actually needed.
The Software
The next step was to start writing the software.
For that I studied tons of similar projects and had to refresh my coding competence.
I had also to update all the software used to write, compile, simulate, etc., and practically had to learn again to use embedded microprocessors.
The result was a long piece of software, coded in C for a 16F877 microprocesor from the PIC family (they are obsolete, but I had a couple in an old drawer...).
I disregarded the Kalman Filter in favor of Complementary Filters to fusion the accelerators and gyroscopes data, to get the actual tilting angles, free from noise (kind of).
Then a PID (Proportional, Integral, Derivative) algorithm produce the PWM (Pulse Width Modulation) signals to be sent to the motor drivers.
When the software was ready enough I bought a 5 degree of freedom (3 accelerometers + 2 gyros) IMU (Inertial Measurement unit) and mounted it together with the microprocessor on a crappy brown perf board, as can be seen in the videos:
Yes, it is true that in the last video it shows a delayed response, but that is due to the lack of adjustment of the software's constants and is already fixed.
Patent Application
To be brief, as I already said I spent several months drafting the Patent Application, that was filed in December 2010 and can be downloaded from this LINK.
May 31, 2011
Problems and Solutions
One problem I find with the Segway is that when running at relatively high speed (compared with a pedestrian), in flat or not banked curves there are lateral forces acting on the driver, which try to take him away from the vehicle.
This causes that the driver must lean laterally enough to avoid falling, and this state is uncomfortable and even dangerous, because the platform keeps horizontal when the terrain is flat.
Even at low speeds, if the terrain is sloping to one side, the platform where the driver stands gets inclined and is uncomfortable and/or unsafe.
The solution I envisioned to solve this problem is a tilting platform, and wheels that also tilt!
But the most important idea is not that the device can tilt sideways, but to add another full inertial system that allows controlling the tilt towards the sides, preventing the vehicle and its driver from falling.
The Segway can not fall to the side (under normal conditions) because it is mechanically rigid in that direction and its center of gravity is over its base of support, but the Tilto does can fall to the sides (it's tilt-able), hence I added a second control system to control this effect.
The result of this second control system is that if the vehicle is moving in a straight line and the driver leans to the right, for example, it produces the left wheel to accelerate and the right wheel to decelerate proportionally (in order to maintainTilto's speed constant) and so the wheels and the vehicle's base will move to the right, changing the overall Tilto's trajectory in that direction and making it to go back to the vertical state (as we would do on a bike for keeping balance , but the Tilto turns by itself!)
Will it work???
Post #1
Tilt and Go...
Tilt'n go
Tilto !
TILTO is an electric unipersonal vehicle of the "Inverted Pendulum" type, balancing automaticallyin two directions simultaneously. The idea came to me in mid-2010 and it took several months to materialize, partly because at that time I was far from home (in Ethiopia) and partly because I decided to write a Patent Application (just in case ...) and it took me a few months.
How did I get the idea of TILTO?
Going VERY early: In talks with friends of mine, long ago, I had discussed the idea of making a mountainboard with "tilting wheels". The tilting wheels idea was mocked was present in several other ideas, but at some point it occurred to me to apply it to a Segway. The Segway is an object of desire for any technophile, and although it's not the universal solution for the transport of persons (according to its makers), it is useful for short trips (I tried one in Paris
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