Recent Embedded System Design Projects :

Battery Management System (BMS) for off grid power

We are currently installing the BMS (Battery Management System) for large LiFePO4 batteries that we have been developing over the past year, aimed specially at off Grid applications such as is required on electric boats.

LiFePO4 batteries were chosen because of their excelent safty record and high longevity. The batteries provide power for the 20kW Electric propulsion motor, and the 10,000VA 230V AC inverter, as well as the cabin lights, radio and other on board equipment.

The Battery Management System is designed especially for this type of off Grid power need, and aims to ensure the maximum longevity of the LiFePO4 batteries. It is closely coupled with the boats Energy management System (EMS) that automatically controls charging.

See the boat at Narrowboat Firecrest at www.nb-Firecrest.co.uk and follow their real life experience as they use our BMS.

This laboratory bottle sampler was Eden Electronic's first use of the WinCE operating system. We configured the operating system using platform builder to the exact requirements of this device. We developed the user interface entirely in C# using the .Net compact framework which gives a simple to use and visually attractive user interface. The user controls all aspects of the test through the colour touch sensitive screen, thus eliminating the need for a keyboard or mouse that could become contaminated in a laboratory environment.

Internally we use an I2C bus to communicate with co-processors that handle the hardware, and provide an interface to a USB memory stick for the export of data to Microsoft Excel, or other such program.

We used a PXA270 processor module to run WinCE and the .NET Compact Framework run time. The control aspects of the software was written in C directly on the WinCE API so that we had deterministic responses.

Throttle Tester :

We developed a production line tester for this and other electronic throttles. The bespoke production line tester guided the factory floor operator through the required setup procedure. Once fully assembled and adjusted the tester performed a series of measurements to ensure the throttle met the specification given by the Engine Control Unit (ECU) manufacture. With a successful test a PASS label is printed. If the device fails the final test then a fault Fault Docket is printed so that the throttle can be repaired.

All the throttle setup and pass criteria are configured by the Production Engineer, giving a simple to use tester for production staff and the flexibility to handle new types of throttles to the on site production engineer.

New life for a legacy 8051 product :

This 8051 based product had been placed on the back burner by our customer thinking that it could not be further enhanced. We performed a few simple optimisation techniques on the software and reduced the code size from 63.5K bytes to just 42K bytes, and at the same time made the software execute quicker.

The optimised software also use less RAM and executed noticeably quicker than the unoptimised software. This new optimised software left ample room for an enhancement that allowed a major contract to be won. We were also able to add new facilities keeping the product competitive.

Contamination Monitor for hydraulic fluid :

This sensor uses laser based technology with an ARM7 processor to measure the contamination levels in hydraulic fluid. The sensor reports the contamination levels to several international standards including NAS1638 and ISO4406:1999, and allows the user to set alarm trigger levels. The sensor can be calibrated with either ACFTD or MTD and is sold world wide.

Internally we use an I2C buss to talk to peripheral devices that control the calibration, LED display, and also the 4-20ma, 0-5 volts, SAE J1939 output options. We also use I2C FRAM chips to hold calibration and other configuration data.

The sensor measures the size of each particle of contamination by measuring the amount of light obscured from the laser. This allows us to count the number of particles and their size, with results being updated every second to give a true online real time monitor of hydraulic fluid contamination. The sensor is designed to be used in-line with hydraulic pressures up to 420 bar.

Optional interface modules for online senor :

After the successful launch of an online sensor, our customer wanted to add a number of optional display and output interfaces. Working with their preferred electronics design houses, we enhancements the embedded software to use the new option boards.

The software automatically detects which option I/O boards are fitted so that it automatically configures itself to use the available interfaces. This eliminated the need for production to configure the device to use the fitted PCBs.

Production line PWM Tester :

We developed a production line tester that measured the frequency, voltage and mark/space ratio of a PWM signal. The tester is used at the end of the production line to make adjustments to the device and to ensure that all the parameters are within the limits defined by their engineers.

The tester is configurable so that the factories production engineer can set the permitted values for each model that they manufacture. The operator has a clear Pass/Fail indication.

Other Recent Projects :- Test & Measurement | Bespoke Testers | Laboratory Equipment | Portable Equipment | PC Software