Here are some of the projects, I have worked on as a freelance developer

GSM remote control of a car heater:

The GSM remote control makes it possible to start car heaters from companies like Webasto and Eberspächer. The car heater is controlled by using voice/data/SMS over the GSM network.

The remote control can be executed using landline phone, mobile phone (voice/SMS) or a smartphone app.

The development of the GSM remote control been done in cooperation with

Remote software/firmware update for embedded devices:

This solution makes it possible to update the software/firmware on embedded devices, which is reachable through wire/GSM/internet. The update is performed using encrypted (AES-256) update files. Updates - including business critical functionality - can confidentially be released without the risk of misuse.

Remote software/firmware update enables the addition of features and bug fixes etc. after installation - without bothering the customer.

The development of remote software/firmware update has been done for 

Large scale production test equipment:

I order to produce a product in larger scale, where quality and traceability is important, a production test equipment has been developed. It minimizes the risk for production errors and at the same time ensures, that the production and test data for each and every device is registered and stored for later analysis.

The production test equipment consists of 1-4 asynchronous operated test stands, each is equipped with a camera for decoding of 2-D QR/DataMatrix code. Every device has a unique code.

A test program (Microsoft .NET, C#) controls the test sequence and ensures, that all test data is stored in a MS SQL database.

When a printed circuit board (PCB) is inserted in or removed from the test stand, the test program starts or stops the test - for easy and fast operation.