Jet Engine Electronic Control Unit
I started this project about September 1999, partly to learn more about jet engines, partly to obtain an ECU that fits mechanically on the circumference of the intake nozzle of my particular engine (Behotec JetStream 66 kit, http://www.behotec.de ), of course for fun, and definately not to save (or earn) money.
If I had spent the time working on this
device on a ďpaid jobĒ, I probably could have bought more than one JetCat Engine...
- providing PWM output to the fuel pump, depending on thrust signal from receiver, current rpm and EGT
- Some of you suggested to add a speed sensor (pitot tube and pressure sensor). I will probably add this feature to the design in a later version. The
circuitry to use a glow-plug for ignition will be added, too.
And now for the most time-consuming part of the ECU (at least to me) - the microcode:
I started writing some basic routines for measuring and scaling of both of the R/C PPM inputs
(Control and Thrust) and also some basic inerrupt structure, all of this with Microchipís MPASM
The schematics and layouts are designed with Target 2001 by IngenieurbŁro Friedrich, they offer an evaluation version of their program on their web page (http://www.ibfriedrich.com) for download. This version should be sufficient for viewing and printing of both schematics and layout, generating parts lists or even exporting netlists to transfer the whole project to another CAD system.
- The PIC 16C73 will be replaced by the PIC 18C252, wich has the same pinout (at least the OTP version) and is so much superior.
- I will probably test the ECU on my turbocharger engine until Iím sure it wonít rip the Jetstream 66 apart.
Progress, progress ;-). You might not have believed that there will be added something to this part of my site ever, but , well, IT WILL! Though not really a breakthrough, but something that will make it much easier for me to continue programming work! I just finished the RS232 transceiver (less the cable) to connect the ECU to a PC. This will make checking individual software modules much easier and straight-ahead.
This transceiver was really not much effort, but it still had to be built. So I hope, if it works correctly, that I will add some news here soon!
Itís been a long time since my last extension to this part of my web site and unfortunately thereís little news about the project. Itís simply that I have too little time to do all the extensive software development by myself. But I had some inquiries for construction information for this project since I removed the files from the server to free up the space. So here they are again:
PicBasic Pro / assembler microcode (still far from completion): Download (14kB)
Some details that have changed: Once again the processor had been changed, now itís a PIC16F876 because of itís electrical erasability. This will speed up software development a lot. I also purchased a copy of ďPicBasic ProĒ by Micro Engineering Labs to simplify programming of the math routines and the sequencing engine. To keep the code fast the interrupt service routines will be kept in assembler. For a new hardware revision I would opt for a separate ignition mechanism so everyone can use the ignition method he prefers (HT spark, glow plug or manual), please see my KJ Starter page for details of a HT ignition module. The ECU would only activate the power to the ignition device.
And once again, please be aware that this is a development project. It is far from being finished, not even usable at all at this time. I would appreciate any and all sopport at developing the microcode for this unit. It wonít need to be written in Basic / assembler but since these are the only programming languages Iím half-way familiar with, I chose them. Donít start building anything to the information above if you expect a fully functional model turbine ECU as a result. Itís still way to go to this point.