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and funding. Tests with real hardware are still often necessary in order to bring research innovations
into common use as affordable consumer devices.
We are trying to find out how the creation of an embedded system could be made both affordable and
maximally easy, so that the building would not require much expertise in electronics (see the analogy
with the PropertyService idea of Maenpaa,Tikanmaki, Riekki & Roning (2004), which enables a non-
robotics expert to use robots in research). Thus, different research results in robotics could be tested by
the researchers themselves easily in a real embedded system. However, the research is not restricted to
robotics, but we try to generalize the results to apply to any research involving embedded systems. We
hope that this research will ultimately expand the utilization of electronics also to non-technical areas
of science, thus giving totally new possibilities for non-technical research.

Our approach
For software development there are many high level languages available, which enable one to create
new software both easily and quickly. One example of them is Microsoft Visual Basic. The ease of use
is obtained mostly by an object-oriented approach, visual aids, and a vast amount of ready-made
lower-level code. For embedded systems there is not such a high level possibility to create new
systems. For hardware development, there are some design methods available, such as Grimpe and
Oppenheimer(2001); Kumar et al (1994); Nebel and Schumacher (1996), which in spite of being
modular or object-oriented require a lot of expertise in electronics. For embedded software, there also
are object-oriented design methods available, some of them even quite innovative, for example Awad,
Kuusela and Ziegler (1996) and Object oriented programmable integrated circuits (OOPIC,
http://www.oopic.com). Object-oriented embedded system development, which covers both software
and hardware design, has been studied by Edwards and Green (2000) in the MOOSE method. Still, the
difficulty level of creating an embedded system continues to be very high compared to many high-
level software development tools. At the other end, there are the robotics system sets by LEGO, which
contain a very easy-to-use user interface and a possibility for fast development of hardware (with Lego
bricks), but due to tightly restricted system, they have limited suitability for testing research results or
creating anything but simple systems.
We have studied how the high-level software language techniques could be applied to the process of
developing an embedded system. We propose an architecture and a development method for embedded
systems that is something between LEGO robotics and extended MOOSE, enabling easy building of
object oriented embedded systems with minimal limitations.

HARDWARE MODEL FOR AN OBJECT-ORIENTED EMBEDDED SYSTEM
DEVELOPMENT METHOD

Introduction
Our method is based on small embedded objects called Atomi-objects. Embedded object means that
the Atomi is an object in both software and hardware (embedded system) aspect. Atomis are small
electronic boards that contain some sensor circuits, actuator drivers, or other functionality. The
software of an Atomi resembles an Automation object (ActiveX Control) by Microsoft. It has
properties, methods, and events that correspond to the physical functionality of the Atomi. In other
words, one can set different properties of an Atomi (such as intensity of a light), run methods (such as
a sequence of positions for a servo), and set an Atomi to respond to events (for example, when heat is
below the threshold in a temperature sensor Atomi, the switch property of a heater Atomi is turned on).
Atomi boards can be stacked together, and they interconnect through a simple field bus that is
extended with a common voltage supply line (see Figure 1). Each board contains a microcontroller unit