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K.I.T,T.I.
Komputerized Instrumentation Technology, Traveling Independently
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   Another revolutionary technology breakthrough from Derrickshouse.com, the people that brought you the MOSVAQC and many other cool ideas and obsene videos. We will soon be introducing the KITTI, a groundbreaking leap forward in the field of feline imitation products.

   Stay Tuned to this page for news flashes and detailed information, including Schematics, DataSheets, really kick-ass code, and performance specifications.

11/27/2002:
  I have the start of a code library developed. Click Here.

11/26/2002:
  After giving up on the Philips I2C harware I've successfully implemented i2c in software on both the 68HC11 and on the PIC boards. In order to get 2 open collector i/o pins to use on the HC11, I had to ditch the keypad, so I'll also be adding a board that gathers keypad input over i2c. The Sonar board has been expanded to handle two sonar modules and I'm able to get both readings to the HC11 over i2c. I will be scrapping the current motor controller that is PIC16F84 based for one that is built on the 16F627. My i2c code will be posted soon. It's pretty sweet.

11/17/2002:
   I haven't updated for a while, there's been a lot of work done, but not much has been accomplished. A 68hc11 eval board (Axiom Mfg. CME-11) has been added which supports a LCD display and 16 digit keypad. To mount the keypad and LCD I made a rear panel out of plexiglass, angled so you can see it from above if you're following the bot. I've spent the bulk of the last week trying to get an i2c bus working between the 68hc11 and the PIC controllers. I initally began to develop the bus entrely in software which did not work out very well. I don't have a osciliscope so debuging the software was very hit or miss, I had no other i2c devices that were known to work. I decided to purchase a hardware solution. After less than sufficient research, I selected the Philips PCF8584 which claims to be bus compatable with the Motorolla 68000 series, which is very similar to the 68hcxx. I have been unable to confirm a successful write to the registers on the controller. I bought an ocsiliscope on ebay which should be here by next weekend, so I've set aside that project for now.
   The sonar modules have been succesfully interfaced with a PIC16F628, which I'm moving all the PIC hardware towards after finding they have more features than the 16F84 yet cheaper, and as a bonus, pin for pin compatable with the 16F84. As of last now I'm working on finalizing the Sonar board to support 2 rangers while leaving the analog comparators inputs open for possible wired joystick input. If I get that done and still don't have my scope yet, I'll interface the sonar module with the motor controller in paralell so i can play around with collision avoidance.

11/04/2002:
   The Pic software for the motor controller is working. There are no inputs yet but I am able to program series of timed directional vectors into the chip and KITTI will move and turn in those directions. I developed a directional matrix that translates from a grid from which direction KITTI want to turn into motor speeds from -3 to +3 for each wheel. When changing speed on either motor the controller will ramp up or down to meet the speed given, only switching the directional relay at the zero crossing. It all looks very smooth.
    I put some ultrasonic sensors and an electonic compas on order over the weekend with should be here next Monday from Acroname , and some more PIC's, resonators and IR Proximity detectors from HVWTech,which should be here Wednesday. I'll be using IR sensors in front of and in back of each drive wheel to keep me from running into things that I cannot climb. An idea that I totally ripped off from Gadget, a very cool robot I came accross on the Web this weekend.

11/01/2002:
   In working on the Pic Controller for the motor drivers I ended up burning up the +5V regulator which sent +12V over to the Pic, frying it as well. The Pic was acting really erraticly, I thought the problem was in the code (the PWM signal is generated in an interrupt [I'll have the code up shortly]), by the time i figured out (more like 'felt', i could see the heat coming off the 7805) what was going on it was too late and the chip was done for. I'm not sure what was causing the overload, It seemed like it was happeneing mostly when the PWM frequency was very high so i'm betting it was caused by a combination of slow switching times in the transistors and the high induction of the motors, I countered the problem by adding a 1000uF capacitor accross each motors and signifcantly extending the pulse with of the Pic output. I also added a 220uF capacitor accross the +12Vin to Gnd on the driver board to take a little stress off the regulator. I pulled all those cap values out of a hat, I like to fantisize that some day I'll sit down and do some math on this project, but not today. Here's the new schematic:


KITTI Motor Controller Revised with Caps and Regulator Detail

10/30/2002:
   I completed the motor driver last night and tested it. I've mounted the Driver and controller boards on Lexan and attached them to KITTI. Tonight I hope to get it wired up and actually get the thing moving around a little. I'm anxious to see how hot the Darlingtons are going to get with 3 Amps going through them. I have some 12V fans on standby if I need them. The PIC controller board is no where near ready so I'll have to use a couple push buttons to control it for now.

10/29/2002:
   I added some links to related material at the bottom of the page, and the way cool photo album at top right. P.S., Don't expect anything on this site to work in Netscape, Opera, or any other whacked out browser that isn't integrated into M$ Windows. Cross-Browser compatablilty is for people with too much time on their hands. Same goes for Netscape users, and I can bad-mouth them all I want here because they probably can't see this page anyway.

10/28/2002:
   Working on Motor Driver Board. Below is the schematic for the current design. I've been through quite a few types of H-Bridge motor drivers before abandoning them and setting on this. I gave up on the H-Bridge because I couldn't come up with a design that was cheap enough without having Huge power losses. I wasn't ready to shell out the cash for Power MOSFETs and charge pump chips to drive them. I need to drive at least 5A through the motors using +5v control lines of < 10 mA. I really want to have two OSMC Boards running the motors but I can't afford them yet (>$300 for pair), so this design should get me by. The plan is to always go to motor stop condition before switching direction with the relay, this should exend the life of the relay dramaticly. 
   The two drivers will be controlled by one PIC16F84 which will recieve speed commands via clocked paralel input. Hopefully i'll have enough pins left to have an encoder input for each wheel.


KITTIE Motor Controller 


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