About this course
Engineer software that must be correct and on time: real-time scheduling, safety-critical design, fault tolerance, and the reliability and certification practices defense systems demand.
Course format. Thirteen weeks, four contact hours each: a two-hour lecture (concepts and theory) and a two-hour practice session. The course is project-based; teams carry one running project end to end and present it three times, in weeks 5, 8, and 13.
What you will build
Built a mission-critical real-time control system on FreeRTOS and an ARM Cortex-M target, implementing rate-monotonic scheduling with proven schedulability, priority-inheritance synchronization, triple-modular redundancy with voting, and a DO-178C-style requirements traceability and structural-coverage evidence package.
Expected outcomes
- Model real-time tasks with periods, deadlines, and worst-case execution times
- Apply rate-monotonic and earliest-deadline-first scheduling and prove schedulability
- Perform response-time analysis and reason about worst-case execution time
- Analyze and bound priority inversion and apply priority inheritance and ceiling protocols
- Design fault-tolerant systems using redundancy, voting, and error detection
- Quantify reliability, availability, and safety with dependability models
- Build hard real-time software on a real-time operating system
- Map software development to certification objectives such as DO-178C
- Evaluate a design against safety requirements with hazard and failure analysis
- Design and defend a complete mission-critical real-time system as a team project
Key topics
- Real-time scheduling
- Safety-critical software
- Fault tolerance & reliability
- Certification standards
Theoretical foundations
The concepts and results this course rests on.
- the periodic task model with periods, deadlines, and worst-case execution times
- rate-monotonic optimality and the Liu and Layland utilization bound
- exact response-time analysis and the schedulability test
- priority inversion and the priority inheritance and ceiling protocols
- the dependability taxonomy of faults, errors, and failures
- redundancy, voting, and the Byzantine agreement problem
- reliability and safety modeling with fault trees and FMEA
Prerequisites
This is a Year-3 course. It assumes the mandatory CS core: data structures and algorithms, operating systems, computer networks, databases, software engineering, and the core mathematics (linear algebra, probability and statistics, calculus, discrete mathematics). It additionally requires the specific prior courses listed below.
Course-specific prerequisites:
- Operating systems
- Embedded or systems programming
- Software engineering
Weekly schedule 13 weeks · lecture + practice
Foundations
Wk 1
Real-time systems and timing
LectureWhat makes a system real-time: hard versus soft deadlines, the task model with periods and deadlines, and why timing correctness is a functional requirement.
PracticeSet up the RTOS toolchain and run periodic tasks, measuring their timing on target hardware.
ProjectRepository, target platform, and periodic tasks with measured timing.
Scheduling
Wk 2
Fixed-priority scheduling
LectureRate-monotonic scheduling and the Liu and Layland utilization bound, optimality of rate-monotonic priority assignment, and the periodic task model.
PracticeAssign rate-monotonic priorities to a task set and verify schedulability against the bound.
ProjectRate-monotonic task set running on the RTOS.
Wk 3
Response-time analysis and EDF
LectureExact response-time analysis from Audsley and colleagues, earliest-deadline-first dynamic scheduling, and the comparison of fixed and dynamic priority.
PracticeCompute worst-case response times for the task set and compare a fixed-priority and an EDF schedule.
ProjectSchedulability analysis report for the project task set.
Wk 4
Resource sharing and priority inversion
LecturePriority inversion, the priority inheritance and priority ceiling protocols of Sha, Rajkumar, and Lehoczky, and bounding blocking time.
PracticeReproduce a priority inversion, then apply priority inheritance and measure the bounded blocking.
ProjectSynchronization with bounded blocking in the system.
Milestone
Wk 5
Specification presentationPresentation
LectureScoping a safety-critical project: the task model, timing requirements, safety requirements, and certification target. Rubric for the specification defense.
PracticeSTUDENT PRESENTATION milestone, specification. Teams present their system concept, the task and timing model, identified hazards and safety requirements, the target certification objectives, and a milestone plan.
ProjectApproved specification with a requirements and timing model.
Timing
Wk 6
Worst-case execution time
LectureWCET analysis, the challenge of caches and pipelines, static versus measurement-based estimation, and why timing predictability matters for safety.
PracticeEstimate WCET for critical tasks with measurement and static analysis and bound the timing.
ProjectWCET bounds feeding the schedulability argument.
Fault tolerance
Wk 7
Redundancy and fault tolerance
LectureFault, error, and failure from the Avizienis dependability taxonomy, redundancy, N-version programming, and triple modular redundancy with voting.
PracticeAdd redundancy and a voter to a critical function and inject faults to test recovery.
ProjectFault-tolerant critical path in the system.
Milestone
Wk 8
Interim demo presentationPresentation
LectureDemonstrating a safety slice: a scheduled, fault-tolerant build meeting deadlines under load.
PracticeSTUDENT PRESENTATION milestone, interim demo. Teams demo the scheduled system meeting its deadlines on target, show timing and overload behavior, and demonstrate fault detection and recovery.
ProjectScheduled, fault-tolerant build meeting deadlines.
Dependability
Wk 9
Reliability and safety modeling
LectureReliability, availability, MTBF, fault trees, failure modes and effects analysis, and quantifying safety integrity.
PracticeBuild a fault tree and an FMEA for the system and compute a reliability estimate.
ProjectReliability and hazard analysis for the design.
Distributed
Wk 10
Distributed fault tolerance and consensus
LectureByzantine faults and the Byzantine generals problem of Lamport, agreement under failure, and time-triggered communication for deterministic distributed systems.
PracticeImplement a fault-tolerant agreement or a time-triggered message schedule across nodes.
ProjectRobust distributed coordination in the system.
Certification
Wk 11
Safety standards and DO-178C
LectureThe certification landscape, DO-178C software levels and objectives, requirements-based testing, structural coverage, and traceability.
PracticeBuild a requirements-to-test traceability matrix and measure structural coverage on critical code.
ProjectCertification evidence package taking shape.
Integration
Wk 12
Verification and the safety case
LectureVerification strategy, the assurance argument and safety case, configuration management, and tool qualification for certified workflows.
PracticeAssemble the safety case and complete verification against the requirements and timing budget.
ProjectVerified system with a safety case ready for the final defense.
Milestone
Wk 13
Final demo and oral defensePresentation
LectureCourse synthesis: from rate-monotonic scheduling to a verified, certifiable safety-critical system and the dependability tradeoffs that defined it.
PracticeSTUDENT PRESENTATION milestone, final demo with oral defense. Teams present the finished system meeting its deadlines on target, walk through scheduling, fault tolerance, and certification evidence, and answer technical questions.
ProjectFinal mission-critical real-time system with certification evidence.
AI tools in this course.
Students use AI assistants and vibe-coding to write and refactor RTOS task code for FreeRTOS or Zephyr, generate scheduling and synchronization scaffolding, and translate response-time and utilization analysis into checkable code. They interact with toolchains and analyzers through assistants and MCP servers that expose the build, the target board, schedulability tools, and coverage tools, asking the model to set up a task set or instrument timing measurements. AI generates requirements-based tests, fault-injection scenarios, and traceability scaffolding for a DO-178C-style evidence package, and helps analyze structural coverage and timing results. Because the code is safety-critical, students rigorously review and independently verify every AI suggestion against timing budgets, schedulability proofs, and the safety requirements.
Student project
Each team builds one mission-critical real-time control or monitoring system across the term on a real-time operating system and target hardware. The project grows weekly from periodic scheduled tasks to a fault-tolerant system with proven schedulability, bounded blocking, reliability analysis, and a DO-178C-style traceability and verification evidence package. The same artifact is presented at the specification, interim, and final milestones.
Requirements
- Build a working system, not a set of disconnected exercises.
- Be original: a new system that solves a real problem, not a re-implementation of a tutorial or course demo.
- Show real depth: real data, real users or realistic load, and engineering trade-offs that are measured rather than assumed.
- Carry one running project from specification to a deployed, defensible result across the whole term.
- Work in a team of three or four and defend the design at each of the three presentations (weeks 5, 8, and 13).
Example projects
Flight-control loop for a small fixed-wing UAVEngine or motor controller with redundant sensingRailway signaling interlock prototypeMedical infusion-pump controllerTriple-redundant attitude estimation nodeAutomotive brake-by-wire control loopTime-triggered distributed sensor network
Assessment & grading
Grading is project-based, with no written exam. Teams of three or four present one running project three times.
| Component | What it covers | Weight |
|---|---|---|
| Project · Specification | Presentation 1 (week 5): problem, objectives, and architecture | 20% |
| Project · Interim | Presentation 2 (week 8): the working system demonstrated live | 30% |
| Project · Final | Presentation 3 (week 13): end-to-end demo with oral defense | 50% |
Tools & platforms
- FreeRTOS: open-source real-time kernel for embedded targets
- Zephyr RTOS: scalable real-time OS for embedded systems
- Ada and SPARK: language and toolset for high-integrity software
- Cheddar: open-source real-time scheduling analysis tool
- STM32 or similar ARM Cortex-M target board
- GNAT and the Ada toolchain for certified development
- AbsInt aiT: static worst-case execution time analysis
- LDRA or VectorCAST: structural coverage and unit testing for DO-178C
- GoogleTest: unit testing of critical components
- Git and a configuration-management workflow for traceability
- Logic analyzer and oscilloscope for timing measurement
- Wireshark with time-triggered protocols for network analysis
Free online courses
Existing free, video-based courses this course can build on, for self-study or as a teaching basis.
- UniversityReal-Time Systems (IIT Kharagpur)
Primary literature
Seminal works to read for graduate-level depth.
- PaperScheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment
- PaperPriority Inheritance Protocols: An Approach to Real-Time Synchronization
- PaperThe Byzantine Generals Problem
- PaperBasic Concepts and Taxonomy of Dependable and Secure Computing
- PaperApplying New Scheduling Theory to Static Priority Pre-emptive Scheduling
References
Books and resources link to an online or publisher page.
- TextbookReal-Time Systems and Programming Languages, 4th Edition
- TextbookHard Real-Time Computing Systems, 3rd Edition
- DocumentationDO-178C Software Considerations in Airborne Systems and Equipment Certification
- DocumentationFreeRTOS Documentation
- DocumentationARINC 653 Part 1 Required Services
- TextbookSafety-Critical Computer Systems
- DocumentationZephyr Project Documentation
Role in each concentration
| Concentration | Role |
|---|---|
| Intelligent Software Systems | Elective |
| Networking & Cyber Security | Elective |
| AI & Robotics | Elective |
| AI and Quantum Computing for Finance | Elective |
| Immersive Systems & Game Development | Elective |
| Defense Technologies & Autonomous Systems | Core · Semester 2 |