| 1. |
- Aidemark, Joakim, 1965, et al.
(författare)
-
Experimental evaluation of time-redundant execution for a brake-by-wire application
- 2002
-
Ingår i: International Conference on Dependable Systems and Networks, 2002. DSN 2002. Proceedings. - 0769511015 ; , s. 210-215
-
Konferensbidrag (refereegranskat)abstract
- This paper presents an experimental evaluation of a brake-by-wire application that tolerates transient faults by temporal error masking. A specially designed real-time kernel that masks errors by triple time-redundant execution and voting executes the application on a fail-stop computer node. The objective is to reduce the number of node failures by masking errors at the computer node level. The real-time kernel always executes the application twice to detect errors, and ensures that a fail-stop failure occurs if there is not enough CPU-time available for a third execution and voting. Fault injection experiments show that temporal error masking reduced the number of fail-stop failures by 42% compared to executing the brake-by-wire task without time redundancy.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Folkesson, Peter, 1968, et al.
(författare)
-
Back-to-Back Fault Injection Testing in Model-Based Development
- 2015
-
Ingår i: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. - 9783319242545 - 9783319242552 ; 9337, s. 135-148
-
Konferensbidrag (refereegranskat)abstract
- Today, embedded systems across industrial domains (e.g., avionics, automotive) are representatives of software-intensive systems with increasing reliance on software and growing complexity. It has become critically important to verify software in a time, resource and cost effective manner. Furthermore, industrial domains are striving to comply with the requirements of relevant safety standards. This paper proposes a novel workflow along with tool support to evaluate robustness of software in model-based development environment, assuming different abstraction levels of representing software. We then show the effectiveness of our technique, on a brake-by-wire application, by performing back-to-back fault injection testing between two different abstraction levels using MODIFI for the Simulink model and GOOFI-2 for the generated code running on the target microcontroller. Our proposed method and tool support facilitates not only verifying software during early phases of the development lifecycle but also fulfilling back-to-back testing requirements of ISO 26262 when using model-based development.
|
|
| 5. |
- Nilsson, Josef, 1981, et al.
(författare)
-
Safe Transitions from Automated to Manual Driving Using Driver Controllability Estimation
- 2015
-
Ingår i: IEEE transactions on intelligent transportation systems (Print). - : Institute of Electrical and Electronics Engineers Inc.. - 1524-9050 .- 1558-0016. ; 16:4, s. 1806-1816
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we consider the problem of assessing when the control of a vehicle can be safely transferred from an automated driving system to the driver. We propose a method based on a description of the driver's capabilities to maneuver the vehicle, which is defined as a subset of the vehicle's state space and called the driver controllability set (DCS). Since drivers' capabilities vary among individuals, the DCS is updated online during manual driving. By identifying the limits of the individual driver's normal driving envelope, we find the estimated bounds of the DCS. Using a vehicle model and reachability analysis, we assess whether the states of the vehicle start and remain within the DCS during the transition to manual driving. Only if the states are within the DCS is the transition to manual driving classified as safe. We demonstrate the estimation of the DCS for four drivers based on the data collected with real vehicles in highway and city driving. Experiments on transitions to manual driving are also conducted with real vehicles. Results show that the proposed method can be implemented with a real system to classify transitions from automated to manual driving.
|
|
| 6. |
- Vedder, Benjamin, 1987-, et al.
(författare)
-
Using Simulation, Fault Injection and Property-Based Testing to Evaluate Collision Avoidance of a Quadcopter System
- 2015
-
Ingår i: 2015 IEEE International Conference on Dependable Systems and Networks Workshops (DSN-W). - Los Alamitos, CA : IEEE Computer Society. - 9781467380447 ; , s. 104-111
-
Konferensbidrag (refereegranskat)abstract
- In this work we use our testing platform based on FaultCheck and QuickCheck that we apply on a quadcopter simulator. We have used a hardware platform as the basis for the simulator and for deriving realistic fault models for our simulations. The quadcopters have a collision-avoidance mechanism that shall take over control when the situation becomes hazardous, steer away from the potential danger and then give control back to the pilot, thereby preventing collisions regardless of what the pilot does. We use our testing platform to randomly generate thousands of simulations with different input stimuli (using QuickCheck) for hundreds of quadcopters, while injecting faults simultaneously (using FaultCheck). This way, we can effectively adjust system parameters and enhance the collision-avoidance mechanism. © 2015 IEEE
|
|
| 7. |
|
|
| 8. |
- Vinter, Jonny, 1963, et al.
(författare)
-
On the Design of Robust Integrators for Fail-Bounded Control System
- 2003
-
Ingår i: Proceedings of the International Conference on Dependable Systems and Networks, San Francisco, CA; United States; 22 June 2003 through 25 June 2003; Code 62415. - Piscataway, NJ : IEEE Communications Society. ; , s. 415-424, s. 415-424
-
Konferensbidrag (refereegranskat)abstract
- This paper describes the design and evaluation of a robust integrator for software-implemented control systems. The integrator is constructed as a generic component in the Simulink design tool, and can thus be used for robust implementation of a wide range of control algorithms. The integrator is designed to support the fail-bounded failure model for transient bit-flips that may occur in the CPU, main memory and I/O circuits of a control system. In particular, it allows the control system to detect and recover from bit-flips that cause data errors. Robustness is achieved by sequentially executing duplicated integrator code on the same processor to support error detection, and through the use of a recovery buffer that allows a roll-back to the previous integrator state when an error is detected. The effectiveness of the robust integrator was evaluated through fault injection experiments with a PI controller, where single bit flips were injected inside the CPU of the control system. No violations of the fail-bounded model were observed in the experiments.
|
|
| 9. |
|
|
| 10. |
- Vinter, Jonny, 1963
(författare)
-
On the Effects of Soft Errors in Embedded Control Systems
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigates techniques for making closed loop control systems fault-tolerant and robust with respect to soft errors occurring in the computer hardware. Soft errors are caused by transient faults that alter the binary values stored in latches, flip-flops and other state elements without causing any permanent damage to the hardware. Soft errors caused by ionizing particles such as high energy neutrons are expected to become a dominating source of hardware failures in future digital circuits. Software implemented techniques for detecting and tolerating soft errors for closed loop control systems are proposed and evaluated. These software techniques are designed to serve as a complement to hardware implemented error detection and correction mechanisms that are present in most computer systems. The objective is to provide a software layer of fault-tolerance mechanisms that can detect, mask or recover from soft errors that escape the hardware mechanisms. Fault injection experiments with control systems for both a four-stroke combustion engine and a jet engine show that a majority of the soft errors (single bit-flips) in CPU-registers and memory have no or minor impact on the behavior of the engines. However, the experiments also show that a small but significant number of the errors result in critical engine failures. These critical failures are predominantly caused by soft errors affecting the state variables of the control algorithm. We present the design and validation of two error detection and recovery techniques called Best Effort Recovery and the Robust Integrator. These techniques are designed to protect the controller state and are experimentally validated by fault injection experiments. The Best Effort Recovery technique performs a rollback recovery if the state variables or the control output are outside defined value bounds. The Robust Integrator is constructed as a generic component in a tool for model-based design and can thus be used for robust implementation of a wide range of control algorithms. To validate these techniques, we have developed a new fault injection tool called GOOFI (Generic Object-Oriented Fault Injection). The tool has been designed to be easily adaptable to different target systems and simple to extend with new fault injection techniques and fault models.
|
|
