Partie interactive du site pédagogique ELECINF344/ELECINF381 de Télécom ParisTech (occurrence 2011).


IRL : Good news !

As you see, yesterday we were having fun with the laser trying to enhance the performances of our smooth text scrolling show. We now have embedded the whole program and it generates directly the ILDA file on board. We still have some speed issues, namely the program which generates the ILDA files is still pretty slow (it takes more than a minute for a tweet), but our imagination is thriving regarding optimization tricks and yet we gained a significant factor on the computing time.

We are also concerned about the beauty of the text. In fact we noticed a few effects in which we’re focusing on :

- When the laser goes more quickly, the line between 2 given points tends to look like a curve Solution : we are going to fix the derangement by adding several intermediate points between our points, this will be done in C at the end of the display chain.

- When the points are too faraway one from another, the galvanometers tend to be more noisy and we tend to be more worried about the survival of our system. Solution : we reduce the size of the text (so as to narrow the space between points) and insert intermediate points between the characters and at the end of the frame to make the shifts of position smoother.

- When the laser isn’t quick enough, we recognized that the flickering effect is more important.
Solution : we need to speed the laser up.

We did some major improvements on those different points not to mention the complexity issues. Step the text is getting more and more beautiful !

I’m sure you want to know a little more about our FPGA. We have enhanced our previous design by adding a RAM FIFO which will allow us to reduce the load of the CPU. We’re working on the CPU’s side of that program. Anyway, our security module seems to be a bit too sensible and it is triggering more often than expected.

In the next few days we will stress on the development of the DMX card.

Sur le même sujet :

  1. IRL : firsts tests with the real laser
  2. IRL : Avancées de la journée
  3. IRL avance sur deux fronts, ILDA et DMX
  4. IRL : choix des composants
  5. Laser, début de l’aventure

1 comment to IRL : Good news !

  • Indeed this is much more readable than before. And when we’ll be using the laser on a larger surface, I’m sure we can fit a few more characters by reducing the font size.