Hello guys,
It has been a while..! I have been writing my MSc thesis and I completely forgot about the blog. Any case I have some good update. The thesis is complete and I suggest you to read it through to understand the techniques used to rule the altitude.
The whole thesis is available at the link http://urn.fi/URN:NBN:fi:tty-201408221388
Today I did some voltage limiter with just two zener and a resistor to both motors.
Now they can work with the voltage provided by the battery pack without problems.
The video shows a sequence of orientations while the motor are spinning with a PWM modulation.It produces a noise that is a kind of irritating but I’m really glad that the things start working.
Nyton will be soon ready to fly!
Well.It seems that Nyton can load 135g!This is the effective load that make the baloon reach the equilibrium(almost).
This test is done with a box that weights 98g(screws included) and some nails that weights about 4,6g each.
I needed 8 nails + the box that is about 135g of load.
It means that the lifting force is equal to 0.135*g so about 1.3Netwon
Hello,
I have been busy and I didn’t write for a while.I’m ending the semester and I have been studying really hard.
Here in Tampere(Finland) days are getting shorter and shorter and the snow is covering the landscape.Santa is getting ready with the presents for all the good kids.
Anyway…my friend Juha Koljonen gave me the first present for Christmas.He has a great, home-made 3d printer and he managed to print some parts I designed with Solidworks.
I eventually found the time to glue the parts and proceed with some test.Well…I needed to fix the tollarances with a file but it seems to work as expected!
Here there is a video that shows how the attidute of the thrust can be chanded.It follows the simulation done with Solidworks.
Simulation becomes reality 🙂
Stay tuned!
It was the spring of 2010.I was in Verres a small village in the Valle d’Aosta region. I had the terrible idea to study Mechatronics engineering and the best place in Italy was that.
It was a period in which I was studying in Politecnico di Torino and I met a random guy called Andrea.We were looking for a flat and we decided to be flat mate.Unfortunatelly for us it was not the right place to make party because the owner suffered a terrible insomnia and so we needed to be fu___in’ silent and quiet (not only during the evening).
Fortunately he had a robot called Sirio, good mechanic but a bit slow.It could react changing path when colliding against objects.In other terms it was a bit like a SumoRobot but really light.
We had a lot of time (sad place for students) and working on it was quite silent apart some hammer blow (and some Andrea’s swearing).
First of all we decided to take apart the old electronics made with an 8 bit MCU and I proposed to use a module that i bough for a handful of €.It was a motor controller form Phidgets (http://www.phidgets.com/products.php?category=19&product_id=1060_0) that now seems to be discontinued.
They gave with the module some API that could be easily used with VisualBasic.net and following the docs I made a simple application to interface them.
As first step, we tried to send some command to the two separated motors.Everything was ok then,next step, why don’t controll it with the keyboard?Ok,just use some DirectX control already in the design tool.Everything works!We could control it intuitively.
Why don’t implement a bluetooth remote control?It is just a matter of emulate a keyboard and the stuff is done.
I was making some experiment during my spare time on something called AForge.net framework(http://www.aforgenet.com/framework/).This is a framework that every programmer can use to fetch images from a webcam and process them with some algorithms already implemented.
I used with a brandless camera that was so chip that I was suprised to see that i was really working.Anyway it was possible to understand the position of some shape in the picture.You just needed a well defined colored object,a filter to isolate that and a function to return the position of the equivalent rectangular after the filtering.
Now there is the interesting part:
We have a robot,we have a control from a pc,we have the image algorithms.
I said :Hei Bulga!Why don’t we merge the pieces?!
It was just enough to make it go on straight if the colored object was in the top of the image and so on for every direction.
We came up with a small robot that could work in three modes:
This is the result:
Stay tuned!
Have you ever though to make an hovercraft?
There are two answers:
Unfortunatelly for you I didn’t make anything even close to a real and heavy machine but I started doing something better.
I just attach a clip that shows my prototipe and I will go through the details of the electronics and the structure in some future post.
How does it work in general?
The prototipe has a sensor that determines the distance from the ground and then a microcontroller commands a current loop that pilots the motor and the propeller.Modifying this flux of air you adjust the height so to keep it as constant as possible even if there are some disturbance.
It has a the loop has a second order dynamic,so in €:it reaches the reference value going above and under it but minimizing the error every time.
After a reasonable time needed to start the motor to a default value the controller starts to work.After a bit I removed some weight and you can see that it can handle a constant disturbance.
In the clip I just complain and swear in some latin language about the power MOSFET because it has a massive overheating.This leads to a terrible stink of metal.At half of that I try to explain something with my deep voice but it was too boring an theoric so maybe I will focus on that later on.
Stay tuned!
Cuverita 