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- El Yaacoub, Ahmed, 1996-, et al.
(författare)
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NeRTA : Enabling Dynamic Software Updates in Mobile Robotics
- 2022
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Konferensbidrag (refereegranskat)abstract
- We present NeRTA (Next Release Time Analysis), a technique to schedule dynamic software updates of the low-level control loops of mobile robots. Dynamic software updates enable software correction and evolution during system operation. In mobile robotics, they are crucial to resolve software defects without interrupting system operation or to enable on-the-fly extensions. Low-level control loops of mobile robots, however, are time sensitive and run on resource-constrained hardware with no operating system support. To minimize the impact of the update process, NeRTA safely schedules updates during times when the computing unit would otherwise be idle. It does so by utilizing information from the existing scheduling algorithm without impacting its operation. As such, NeRTA works orthogonal to the existing scheduler, retaining the existing platform-specific optimizations and fine-tuning, and may simply operate as a plug-in component. Our experimental evaluation shows that NeRTA estimates are within 15% of the actual idle times in more than three-quarters of the cases. We also show that the processing overhead of NeRTA is essentially negligible.
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| 2. |
- El Yaacoub, Ahmed, et al.
(författare)
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Poster Abstract: Scheduling Dynamic Software Updates in Safety-critical Embedded Systems : the Case of Aerial Drones
- 2022
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Ingår i: 2022 ACM/IEEE 13th International Conference on Cyber-Physical Systems (ICCPS). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781665409674 - 9781665409681 ; , s. 284-285
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Konferensbidrag (refereegranskat)abstract
- Dynamic software updates enable software evolution and bug fixes to embedded systems without disrupting their run-time operation. Scheduling dynamic updates for safety-critical embedded systems, such as aerial drones, must be done with great care. Otherwise, the system's control loop will be delayed leading to a partial or even complete loss of control, ultimately impacting the dependable operation. We propose an update scheduling algorithm called NeRTA, which schedules updates during the short times when the processor would have been idle. NeRTA consequently avoids the loss of control that would occur if an update delayed the execution of the control loop. The algorithm computes conservative estimations of idle times to determine if an update is possible, but is also sufficiently accurate that the estimated idle time is typically within 15% of the actual idle time.
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| 3. |
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| 4. |
- El Yaacoub, Ahmed, 1996-, et al.
(författare)
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Scheduling Dynamic Software Updates in Mobile Robots
- 2023
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Ingår i: ACM Transactions on Embedded Computing Systems. - : Association for Computing Machinery (ACM). - 1539-9087 .- 1558-3465. ; 22:6, s. 1-27
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Tidskriftsartikel (refereegranskat)abstract
- We present NeRTA (Next Release Time Analysis), a technique to enable dynamic software updates for low-level control software of mobile robots. Dynamic software updates enable software correction and evolution during system operation. In mobile robotics, they are crucial to resolve software defects without interrupting system operation or to enable on-the-fly extensions. Low-level control software for mobile robots, however, is time sensitive and runs on resource-constrained hardware with no operating system support. To minimize the impact of the update process, NeRTA safely schedules updates during times when the computing unit would otherwise be idle. It does so by utilizing information from the existing scheduling algorithm without impacting its operation. As such, NeRTA works orthogonal to the existing scheduler, retaining the existing platform-specific optimizations and fine-tuning, and may simply operate as a plug-in component. To enable larger dynamic updates, we further conceive an additional mechanism called bounded reactive control and apply mixed-criticality concepts. The former cautiously reduces the overall control frequency, whereas the latter excludes less critical tasks from NeRTA processing. Their use increases the available idle times. We combine real-world experiments on embedded hardware with simulations to evaluate NeRTA. Our experimental evaluation shows that the difference between NeRTA’s estimated idle times and the measured idle times is less than 15% in more than three-quarters of the samples. The combined effect of bounded reactive control and mixed-criticality concepts results in a 150+% increase in available idle times. We also show that the processing overhead of NeRTA and of the additional mechanisms is essentially negligible.
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