Certifiable to DO-178B Level A, BAE SYSTEMS’ second-generation CsLEOS real-time operating system provides integrated fault-tolerant and hard real-time capabilities that suit it for a range of military and aerospace applications.
Using hardware memory protection, CsLEOS provides complete time, space, and resource partitioning between the kernel and applications operating on the same hardware platform. It also provides guaranteed resource availability in both the time and space domains. This combination facilitates the robust partitioning defined in ARINC 653, enabling applications with different DO-178B safety levels to run concurrently on the same processor. CsLEOS also supports ‘on-the-fly’ application rescheduling, giving it the flexibility needed to meet a broad range of dynamic safety-critical applications.
To guarantee fast recovery for time-critical events without compromising system safety, CsLEOS synchronises all redundant channels on a frame-by-frame, lock-step basis, ensuring that all channels process the same data concurrently. In the event of a fault on one of the channels, the RTOS restarts the channel (‘fast restart’) within milliseconds.
To further enhance fault tolerance, CsLEOS provides a built-in health monitor. Unlike approaches that require system responses to be hand-coded into the application, CsLEOS allows developers to define their applications’ responses to faults and store them separately in configuration tables. This approach enhances flexibility and guarantees that faults will be resolved reliably and in a timely fashion.
To streamline application development, upgrades, and D0-178B certification, CsLEOS supports independent loading of application modules. Unlike approaches in which a portion of the kernel must be linked to each application, CsLEOS interacts exclusively with applications through its Applications Programming Interface. This enables existing applications to be modified and new applications to be built and installed without the entire system having to be recompiled and rebuilt. This flexibility makes the system less expensive to test, certify, and maintain, greatly reducing life-cycle costs.
CsLEOS provides industry-standard OpenGL graphics drivers that allow developers to build 3-D interfaces for mission-critical applications such as synthetic vision systems that allow aircraft to land in adverse weather. Moreover, the system’s graphics drivers do not require a separate host processor, but run on the same hardware platform with safety-critical flight applications without interfering with them.
BAE SYSTEMS supports a wide variety of third-party development tools, including DDC-I’s SCORE653 RTOS-aware integrated development environment.
The company also has signed an agreement with Dy 4 Systems to offer the RTOS on its PowerPC single-board computers, which are optimised for applications that demand adherence to rigid safety standards.
Development seats for the CsLEOS RTOS are available beginning at $50,000.