Real-time Embedded Applications Research Articles

A joystick driving control algorithm with a longitudinal collision avoidance scheme for an electric vehicle

In this paper, we develop a joystick manual driving algorithm for an electric vehicle called Cycab. Cycab is developed as a public transportation vehicle, which can be driven either by a manual joystick or an automated driving mode. The vehicle uses six motors for driving four wheels, and front/rear steerings. Cycab utilizes one industrial PC with a real time Linux kernel and four Motorola MPC555 micro controllers, and a CAN network for the communication among the five processors. The developed algorithm consists of two automatic vehicle speed control algorithms for normal and emergency situations that override the driver’s joystick command and an open loop torque distribution algorithm for the traction motors. In this study, the algorithm is developed using SynDEx, which is a system level CAD software dedicated to rapid prototyping and optimizing the implementation of real-time embedded applications on distributed architectures. The experimental results verify the usefulness of the two automatic vehicle control algorithms.

Crafting a Java virtual machine in silicon

The aJile family of low-power, single-chip, embedded Java microcontrollers provides an efficient platform for embedded and real-time Java execution. The aJile CPU hardware provides direct support for the entire JVM instruction set and thread model, obviating the need for a Java interpreter or just-in-time compiler, as well as the traditional RTOS. aJile's hardware technology also supports multiple JVM contexts executing on the same CPU, enhancing safety and security by guaranteeing space and time allotments for multiple Java applications. Combined with a Java 2 Micro Edition (J2ME) runtime and a back-end target build tool, these technologies allow the development of real-time embedded applications entirely in Java.

A methodology and toolset for the design of parallel embedded systems

Real-time embedded applications such as signal-processing, surveillance and tracking, data fusion, and automated target recognition need parallel processors to meet their performance requirements. Unfortunately the task of developing the application-software, which must not only make efficient use of the available parallelism but must also integrate the many algorithms that comprise it, is extremely difficult. Current software design methods, including object oriented design methods, do not help in this regard as they are geared primarily for the design of sequential software.This paper presents an overview of the Parallel Scalable Design Toolset (PSDT) being developed at Honeywell to support the design and development of real-time embedded parallel software. Software designers can use PSDT to graphically specify parallelism across collections of objects and within objects, and synchronization of data and control flows. They can also compose parallel subtasks into tasks that may in turn be a part of other tasks.PSDT can support different domain-specific parallelization paradigms. Each paradigm defines composition rules and constraints on inter- and intra-object parallelism. Since domain-specific paradigms add additional structure to the program, tools for parallelism analysis, partitioning, mapping, and code generation are able to produce near-optimum results.A prototype of the PSDT toolset is operational including a domain-specific paradigm for deterministic data-parallel periodic applications. Support for other domains and heterogenous processing architectures is being added.