Midnight and the tweaking of stop and going

Today started badly when I couldn’t get my Titanium Powerbook to use the wireless connection reliably. I had a 10.3 beta installed on so I thought maybe that was the problem. I tried to update to the latest beta (since Apple didn’t have the downgrader for the version I had installed on their site any more) but after I finished updating the dumb thing panicked every time it booted. So there went all my programming ideas. I pretty much tried to just help out whoever needed it.

I discussed logging and log visualizations with Jim. I’m going to write an OpenGL program to parse the log file from Jim’s main control loop and display all the pieces of information in nice graphical form. Right now we just have ascii-art for the LADAR visualizations and we haven’t even got the radar power supply worked out yet. As cool as the ascii-art is, I feel we can get a better representation of the data with and nice OpenGL app.

Jim and I discussed adding accelerators for the gas pedal so that the gas pedal doesn’t get floored when you tell the car to go 20mph from a dead stop. We want it to go nice and smoothly like you do when you accelerate from a intersection after a red light (assuming you are not racing the guy next to you).

I had to replace a power supply after Rob put together the radar computer for us. After that we got it to boot and installed RealVNC on it so that we could run it headless (it has to run windows).

At some point we were out during to test the truck when the Kill Switch system failed and shut down the car. Jim had to phone Josh and make him drive down to us and bypass the kill switch hardware so we could get out of the road. Oy!

The most memorable part of today was when we tested the servo system. From about 12am to 3am We drove all around El Segundo and on PCH from Manhattan beach to past LAX at 15 MPH. The first half of the time we were testing the throttle servo system and tweaking all the constants so that the system didn’t overshoot too much and so it was generally responsive.

The exciting parts came at the beginning when we discovered a wrapping bug that caused the servo to go full throttle when we least expected it! Luckily Jim was fast with the servo override switch and all that happened was that we got a little scared. I must say it’s a very strange feeling to be tweaking parameters on a control system that you also happen to be a passenger in — I was very tense at first but it was strangely exhilarating.

Testing the brakes was just as exciting, especially the very first time. We just did a full brake to see what it could handle. We had the pressure tweaked so that there was no skidding, just a nice, if slightly heavy footed, deceleration.

We kept driving past police cars and desperately hoping that they wouldn’t pull us over. Luckily none ever did.

Jim wanted to test the steering control, but we decided we were both too tired and so we called it a night.

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