Impact of clock drifts on CAN frame response time distributions

Sensor networks require a high degree of synchronization in order to produce a stream of data useful for further purposes. Examples of time misalignment manifest as undesired artifacts when doing multi-camera bundle-adjustment or global positioning system (GPS) geo-localization for mapping. Network Time Protocol (NTP) variants of clock synchronization can provide accurate results, though present high variance conditioned by the environment and the channel load. We propose a new precise technique for software clock synchronization over a network of rigidly attached devices using gyroscope data. Gyroscope sensors, or IMU, provide a high-rate measurements that can be processed efficiently. We use optimization tools over the correlation signal of IMU data from a network of gyroscope sensors. Our method provides stable microseconds accuracy, regardless of the number of sensors and the conditions of the network. In this paper, we show the performance of the gyroscope software synchronization in a controlled environment, and we evaluate the performance in a sensor network of smartphones by our open-source Android App, Twist-n-Sync, that is publicly available.

show abstract

“…The re-synchronization period may be significantly increased if the time drift can be compensated by other techniques (e.g., Reference [ 45 ]).…”

Section: Experiments On Uncontrolled Conditions: Smartphonesmentioning

confidence: 99%

Twist-n-Sync: Software Clock Synchronization with Microseconds Accuracy Using MEMS-Gyroscopes

Faizullin

Kornilova

Akhmetyanov

et al. 2020

Sensors

View full text Add to dashboard Cite

show abstract

“…Although in the automotive domain jitters on the order of a millisecond-mainly caused by interference from higher-priority messages-are routinely acceptable [6,15], jitter is recognized as a key timing parameter in general [8,25] and several other applications of practical interest, such as the ones referenced in [16][17][18][19][20] are sensitive to it. This is why a number of techniques have appeared in the literature, which aimed at granting a higher level of determinism in networked embedded control systems by addressing the main sources of CAN communication jitters, namely, interference and bit stuffing.…”

Section: Introductionmentioning

confidence: 99%

Performance evaluation and improvement of the CPU-CAN controller interface for low-jitter communication

Cena

Bertolotti

et al. 2012

Proceedings of 2012 IEEE 17th International Conference on Emerging Technologies &Amp; Factory Automation (ETFA 2012)

View full text Add to dashboard Cite

The effectiveness and quality of several distributed control loops are heavily affected by the ability to reduce jitters. This goal can hardly be achieved without understanding all possible causes that can introduce time fluctuations in the communication path between the processor, running the control algorithms, and the (remote) peripheral devices. This is because any of them, in fact, may worsen the timing accuracy of the system as a whole.After the most well-known sources of jitters are put under control, other aspects become more and more important for the overall behavior of the system. This paper tackles the problem of time fluctuations introduced by the interface between the Central Processing Unit (CPU) and the CAN controller in a typical off-the-shelf, single-chip microcontroller and shows why and how they should be considered and handled carefully.

show abstract

“…In addition, changing environmental conditions, such as temperature or EMI, will affect the functioning of the system. For instance, significant clock drifts are caused by varying temperatures [9]. Completely time-deterministic systems as defined in [5] are thus hard to achieve.…”

Section: Timing Determinism and Timing Correctnessmentioning

confidence: 99%

Towards a declarative modeling and execution framework for real-time systems

Altmeyer

Navet

2016

SIGBED Rev.

Self Cite

View full text Add to dashboard Cite

Our work is a contribution towards addressing what Thomas Henziger called the grand challenge in embedded software design [5]: "offering high-level programming models that exposes the execution properties of a system in a way that permits the programmer to express desired reaction and execution requirements, permits the compiler and run-time systems to ensure that these requirements are satisfied". In the programming model we describe here, the developer states the permissible timing behavior of the system, a system synthesis step involving both analysis and optimization generates a scheduling solution which at run-time is enforced by the execution environment. With respect to the synchronous programming models, our approach implements a weaker version of time-determinism, still providing a form of timing-predictability sufficient in many applications while remaining closer to mainstay software development practices. This approach is currently being implemented and experimented in the CPAL language development tools and associated runtime environment.

show abstract

Impact of clock drifts on CAN frame response time distributions

Cited by 16 publications

References 10 publications

Twist-n-Sync: Software Clock Synchronization with Microseconds Accuracy Using MEMS-Gyroscopes

Twist-n-Sync: Software Clock Synchronization with Microseconds Accuracy Using MEMS-Gyroscopes

Performance evaluation and improvement of the CPU-CAN controller interface for low-jitter communication

Towards a declarative modeling and execution framework for real-time systems

Contact Info

Product

Resources

About