In this note, we revisit the problem of scheduling stabilizing control tasks on embedded processors. We start from paradigm that a real-time scheduler could be regarded as feedback controller decides which task is executed at any given instant. This has for objective guaranteeing (control unrelated) software meet their deadlines and asymptotically stabilize plant. investigate simple event-triggered based show how it leads to guaranteed performance thus relaxing more traditional periodic...

Recent developments in computer and communication technologies have led to a new type of large-scale resource-constrained wireless embedded control systems. It is desirable these systems limit the sensor computation and/or instances when system needs attention. However, classical sampled-data based on performing sensing actuation periodically rather than This paper provides an introduction event- self-triggered where performed needed. Event-triggered reactive generates sampling when, for...

The vast majority of today's critical infrastructure is supported by numerous feedback control loops and an attack on these can have disastrous consequences. This a major concern since modern systems are becoming large decentralized thus more vulnerable to attacks. paper concerned with the estimation linear when some sensors or actuators corrupted attacker. In first part we look at problem where characterize resilience system attacks study possibility increasing its change parameters. We...

This paper provides an introduction and overview of recent work on control barrier functions their use to verify enforce safety properties in the context (optimization based) safety-critical controllers. We survey main technical results discuss applications several domains including robotic systems.

Feedback control laws have been traditionally implemented in a periodic fashion on digital hardware. Although periodicity simplifies the analysis of mismatch between design and its implementation, it also leads to conservative usage resources such as CPU utilization case embedded control. We present novel technique that abandons assumption by using current state plant decide next time instant which should be measured, law computed, actuators updated. This technique, termed self-triggered...

This paper develops a control methodology that unifies barrier functions and Lyapunov through quadratic programs. The result is demonstrated on adaptive cruise control, which presents both safety performance considerations, as well actuator bounds. We begin by presenting novel notion of function associated with set, formulated in the context Lyapunov-like conditions; existence satisfying these conditions implies forward invariance set. formulation naturally yields (CBF), yielding inequality...

Event-triggered control consists of closing the feedback loop whenever a predefined state-dependent criterion is satisfied. This paradigm especially well suited for embedded systems and networked since it able to reduce amount communication computation resources needed control, compared traditional periodic implementation. In this paper, we propose framework event-triggered stabilization nonlinear using hybrid tools, that general enough encompass most existing techniques, which revisit...

Event-triggered control has been recently proposed as an alternative to the more traditional periodic execution of tasks. In a typical event-triggered implementation, signals are kept constant until violation condition on state plant triggers recomputation signals. The possibility reducing number recomputations, and thus transmissions, while guaranteeing desired levels performance, makes very appealing in context sensor/actuator networks. particular, by network traffic we also reduce energy...

Safety critical systems involve the tight coupling between potentially conflicting control objectives and safety constraints. As a means of creating formal framework for controlling this form, with view toward automotive applications, paper develops methodology that allows conditions-expressed as barrier functions-to be unified performance objectives-expressed Lyapunov functions-in context real-time optimization-based controllers. conditions are specified in terms forward invariance set,...

This paper describes two algorithms for state reconstruction from sensor measurements that are corrupted with sparse, but otherwise arbitrary, "noise." These results motivated by the need to secure cyber-physical systems against a malicious adversary can arbitrarily corrupt measurements. The first algorithm reconstructs batch of while second is able incorporate new as they become available, in spirit Luenberger observer. A distinguishing point these use event-triggered techniques improve...

Switched systems constitute an important modeling paradigm faithfully describing many engineering in which software interacts with the physical world. Despite considerable progress on stability and stabilization of switched systems, constant evolution technology demands that we make similar respect to different, perhaps more complex, objectives. This paper describes one particular approach address these different objectives based construction approximately equivalent (bisimilar) symbolic...

The control of complex systems poses new challenges that fall beyond the traditional methods theory. One these is given by need to control, coordinate and synchronize operation several interacting submodules within a system. desired objectives are no longer captured usual specifications such as stabilization or output regulation. Instead, we consider linear temporal logic (LTL) formulas. We show existence controllers for discrete-time controllable LTL can be decided effectively computed....

Barrier functions (also called certificates) have been an important tool for the verification of hybrid systems, and also played roles in optimization multi-objective control. The extension a barrier function to controlled system results control function. This can be thought as being analogous how Sontag extended Lyapunov order enable controller synthesis stabilization tasks. A enables safety requirements specified by forward invariance set using Lyapunov-like condition. paper develops...

Finite-state models of control systems were proposed by several researchers as a convenient mechanism to synthesize controllers enforcing complex specifications. Most techniques for the construction such symbolic have two main drawbacks: either they can only be applied restrictive classes systems, or require exact computation reachable sets. In this paper, we propose new abstraction technique that is applicable any nonlinear sampled-data system long are interested in its behavior compact...

Secure state estimation is the problem of estimating a dynamical system from set noisy and adversarially corrupted measurements. Intrinsically combinatorial problem, secure has been traditionally addressed either by brute force search, suffering scalability issues, or via convex relaxations, using algorithms that can terminate in polynomial time but are not necessarily sound. In this paper, we present novel algorithm uses satisfiability modulo theory approach to harness complexity...

The interaction between information technology and phys ical world makes Cyber-Physical Systems (CPS) vulnerable to malicious attacks beyond the standard cyber attacks. This has motivated need for attack-resilient state estimation. Yet, existing state-estimators are based on non-realistic assumption that exact system model is known. Consequently, in this work we present a method estimation presence of attacks, systems with noise modeling errors. When estimated states used by state-based...

Event-triggered and self-triggered control have been recently proposed as an alternative to the more traditional periodic execution of tasks. The possibility reducing number executions while guaranteeing desired levels performance makes event-triggered very appealing in context sensor/actuator networks. In this setting, times that a feedback law is executed implies reduction transmissions thus energy expenditures. paper we introduce two novel distributed implementations policies over...

This paper develops a control approach with correctness guarantees for the simultaneous operation of lane keeping and adaptive cruise control. The safety specifications these driver assistance modules are expressed in terms set invariance. Control barrier functions (CBFs) used to design family solutions that guarantee forward invariance set, which implies satisfaction specifications. CBFs synthesized through combination sum-of-squares program physics-based modeling optimization. A real-time...

Symbolic models are abstract descriptions of continuous systems in which symbols represent aggregates states. In the last few years there has been a growing interest use symbolic as tool for mitigating complexity control design. fact, enable well-known algorithms context supervisory and algorithmic game theory controller synthesis. Since 1990s many researchers faced problem identifying classes dynamical that admit models. this paper we make further progress along research line by focusing on...