Software & Embedded electronics

Fuel Injector Flow Bench

peterdahlman — Wed, 21 Dec 2011 07:50:25 +0000

Currently working on a PC-Controlled Fuel Injector Flow Bench.

Static, Step, Simultaneous, Alternating and Dynamic test modes with timing
USB Interface (RS232 Conversion)
Temperature, Voltage and AMP monitoring
Adjustable system pressure of 0-6 Bar
Windows operator software written in C#
AVR8 based controller board (@8 MHz) with 4 separate injector drivers

Soldered the components on a prototype board

The wiring harness is far from optimal but will do the trick until i get some better cables.

Validating an early version of the PC and embedded controller software:
(The timing was not 100% calibrated and microcontroller running @ 1MHz)

Later versions of the controller board runs at @ 8MHz for better precision.

Playing around (This is called validation right?)

Mechanical construction

This is pretty much what got me the initial ideas for the machine

This regulator will allow an adjustable system pressure of 0-6 bar

Made this stand to secure injectors to the fuel rail:

Fuel tank (With in-tank fuel pump and filter)

Took a while to (TIG) weld the tank

Luckily the tank turned out to seal well when i performed a pressure test

The machine is going to turn out something like this

Fuel tank and fuel pump armature completed.

Tried out the new measuring cylinders

Fuel pump and filter assembly

Added the AN-fittings

First test runs

Power and fuel pump control.
Displays temperature, voltage and current.
Besides the controller board there’s a fuel pump relay, current monitor power source , polarity protection diodes and fuses.

To be continued…

Square wave generator with interference simulation

peterdahlman — Thu, 05 May 2011 13:18:55 +0000

Recently, i needed to test a circuit we’ve been working on for quite a while.
Shocked by the prices of available AWG’s, i decided to make one my self using the sound card output of the PC.

This software might be useful when designing wheel decoders or other types of time critical devices.

Features:

Frequency by Hertz or Periods per minute (RPM)
Frequency scope (Linear by total of periods)
No of pulses
Missing pulses
No of periods
Interference simulation
Free as in Beer

You can download the software here!

NOTE: This is an über alpha version, so please don’t expect to much

Access & rental service for truck maintenance hall

peterdahlman — Wed, 25 Nov 2009 21:20:41 +0000

A small system used for access and power control of a truck maintenance hall.
In addition to this functionality, the unit also provides invoice documents and transaction logs on company/employee basis.
The invoice documents and transaction logs are accessible remotely through a web interface, were the administrator also actually can control the maintenance hall remotely.

This system i based on the ACME circuit board with a recompiled kernel supporting the webserver Apache and another board for electrical contactor control and pinpad interface. The admin web interface is written in PHP and uses SqLite, wich both resides onboard the unit.
Device drivers and main logic is written in C.

Here’s a picture of the system while still under development (in case that isn’t obvious )

I will update this article with some more information and pictures of the system in use.

Megasquirt Dashlogger

peterdahlman — Tue, 24 Nov 2009 10:24:52 +0000

Made a dashlogger for the Megasquirt electronic fuel injection system.
Supports runtime log directly to a FAT32 formated USB memory stick.
This system is based on the ACME board and a couple of other more standard like components.
The software is written in C and Assembly. All set up in a pretty ugly hombrewed TIG-welded chassi.

First i made an desktop prototype with a fancy O-LED color display:

I choosed to switch for a simpler display type because of the
price range of the O-LED’s. Not as fancy as the prototyped one, but it get’s the work done.

And the quite nasty chassi…

I will add more info about this later on…