The Chimera II real-time operating system for advanced sensor-based control applications

Stewart, David B.; Schmitz, D.E.; Khosla, Pradeep K.

doi:10.1109/21.199456

Cited by 89 publications

(24 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is ROMable and scalable (only modules that are needed are compiled into the execu- ECHIDNA: A cooperative multitasking RTOS based on Chimera [36] that swaps Chimera's POSIX-like threads in the microkernel for port-based objects [37]; it supports reconfigurable component-based software for microcontrollers and digital signal processors [12]. This is chosen to be representative of sophisticated dynamic-priority cooperative RTOSs with footprints small enough for microcontroller systems (Echidna has a footprint of~6KB).…”

Section: Methodsmentioning

confidence: 99%

“…Echidna is a scaled down version of the Chimera RTOS [36] that replaces Chimera's concept of a process (which is notionally similar to that of POSIX threads) with port-based objects [37]. It is designed to support dynamically reconfigurable real-time software and is targeted for 8-bit to 32-bit microcontrollers as well as DSPs, whereas Chimera was intended for 32-bit multiprocessor systems due to its relatively high overhead.…”

Section: The Echidna Rtosmentioning

confidence: 99%

See 1 more Smart Citation

The performance and energy consumption of embedded real-time operating systems

Baynes

Collins

Fiterman³

et al. 2003

IEEE Trans. Comput.

View full text Add to dashboard Cite

Abstract-This paper presents the modeling of embedded systems with SimBed, an execution-driven simulation testbed that measures the execution behavior and power consumption of embedded applications and RTOSs by executing them on an accurate architectural model of a microcontroller with simulated real-time stimuli. We briefly describe the simulation environment and present a study that compares three RTOSs: C/OS-II, a popular public-domain embedded real-time operating system; Echidna, a sophisticated, industrial-strength (commercial) RTOS; and NOS, a bare-bones multirate task scheduler reminiscent of typical "roll-your-own" RTOSs found in many commercial embedded systems. The microcontroller simulated in this study is the Motorola M-CORE processor: a low-power, 32-bit CPU core with 16-bit instructions, running at 20MHz. Our simulations show what happens when RTOSs are pushed beyond their limits and they depict situations in which unexpected interrupts or unaccounted-for task invocations disrupt timing, even when the CPU is lightly loaded. In general, there appears no clear winner in timing accuracy between preemptive systems and cooperative systems. The power-consumption measurements show that RTOS overhead is a factor of two to four higher than it needs to be, compared to the energy consumption of the minimal scheduler. In addition, poorly designed idle loops can cause the system to double its energy consumption-energy that could be saved by a simple hardware sleep mechanism.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: The Echidna Rtosmentioning

confidence: 99%

The performance and energy consumption of embedded real-time operating systems

Baynes

Collins

Fiterman³

et al. 2003

IEEE Trans. Comput.

View full text Add to dashboard Cite

show abstract

“…The mechanisms can be used with a variety of common scheduling algorithms, and serve as the basis for easily extending these policies to incorporate aperiodic servers, soft real-time threads, imprecise computations, and adaptive real-time scheduling. The mechanisms have been incorporated into the Chimera RTOS [9].…”

Section: Introductionmentioning

confidence: 99%

Mechanisms for detecting and handling timing errors

Stewart

Khosla

1997

Commun. ACM

View full text Add to dashboard Cite

“…Visual programming tools are very desirable in this regard, since they should provide an intuitive w ay to link modules. We rely on the important b a c kground acquired developing the CHIMERA 22 OS and the ONIKA 23 visual interface. Strategies for learning.…”

Section: Conclusion { Future Workmentioning

confidence: 99%

<title>Modified reactive control framework for cooperative mobile robots</title>

et al. 1997

View full text Add to dashboard Cite

An important class of robotic applications potentially involves multiple, cooperating robots: security or military surveillance, rescue, mining, etc. One of the main challenges in this area is e ective cooperative control: how does one determine and orchestrate individual robot behaviors which result in a desired group behavior? Cognitive (planning) approaches allow for explicit coordination between robots, but su er from high computational demands and a need for a priori, detailed world models. Purely reactive a p p r o a c hes such as that of Brooks are e cient, but lack a mechanism for global control and learning. Neither approach b y itself provides a formalism capable of a su ciently rapid and rich range of cooperative b e h a viors. Although we accept the usefulness of the reactive paradigm in building up complex behaviors from simple ones, we seek to extend and modify it in several ways. First, rather than restricting primitive b e h a viors to xed input-output relationships, we include memory and learning through feedback adaptation of behaviors. Second, rather than a xed priority of behaviors, our priorities are implicit: they vary depending on environmental stimuli. Finally, w e scale this modi ed reactive a r c hitecture to apply not only for an individual robot, but also at the level of multiple cooperating robots: at this level, individual robots are like individual behaviors which c o m bine to achieve a desired aggregate behavior. In this paper, we describe our proposed architecture and its current implementation. The application of particular interest to us is the control of a team of mobile robots cooperating to perform area surveillance and target acquisition and tracking.

show abstract

The Chimera II real-time operating system for advanced sensor-based control applications

Cited by 89 publications

References 17 publications

The performance and energy consumption of embedded real-time operating systems

The performance and energy consumption of embedded real-time operating systems

Mechanisms for detecting and handling timing errors

<title>Modified reactive control framework for cooperative mobile robots</title>

Contact Info

Product

Resources

About