Abstract: According to some embodiments, an Arbitrary Software Logic Modeling (“ASLM”) data source may store electronic records associated with units, each electronic record including a unit identifier, one or more identification tags, context data, unit parameters, unit variables, and internal logic. An ASLM platform may express system requirements at a logic block level and establish the logic blocks as self-contained entities and connections in accordance with the system requirements (the established logic blocks graphically representing systems logic). The ASLM platform may then explicitly transform the systems logic automatically to output language agnostic common design information exchange model information. The ASLM platform may also translate and maintain traceability among the system requirements, common design information exchange model information, and generated code.

Abstract: A method for model-based design of safety-critical software is disclosed. The method includes receiving natural-language software requirements, developing a specification model by implementing either semantic modeling or graphical modeling, applying formal requirements analysis to the specification model, auto generating requirements based and robustness test cases from the specification model, developing a design model based on the specification model, applying test cases to the design model, auto-generating source code using the design model, verifying the source code using both test cases and static analysis technology, and compiling executable object code from the verified source code. If a result of the analysis of the software specification or design models is not satisfactory then adjusting the specification or design model to correct any inconsistency, and repeating applying the analysis and test cases.

Abstract: A computer-implemented system for generating test cases and/or test procedures to verify software having a nonlinear arithmetic constraint over a Real number range. The system includes a translator that receives, as input, software specification models for the software to be verified. The translator is configured to generate, as output, a plurality of SMT formulas that are semantically equivalent to the software specification models. The system includes an analytical engine pool that receives, as input, the plurality of SMT formulas from the translator and analyzes the plurality of SMT formulas, and generates, as output, test case data for each of the plurality of SMT formulas determined to be satisfiable. The system includes a post-processor that receives, as input, the test case data from the analytical engine pool and generates, as output, the test cases and/or test procedures for the software to be verified based on the test case data.

Abstract: According to some embodiments, an Arbitrary Software Logic Modeling (“ASLM”) data source may store electronic records associated with units, each electronic record including a unit identifier, one or more identification tags, context data, unit parameters, unit variables, and internal logic. An ASLM platform may express system requirements at a logic block level and establish the logic blocks as self-contained entities and connections in accordance with the system requirements (the established logic blocks graphically representing systems logic). The ASLM platform may then explicitly transform the systems logic automatically to output language agnostic common design information exchange model information. The ASLM platform may also translate and maintain traceability among the system requirements, common design information exchange model information, and generated code.

Abstract: A method for automated test case augmentation includes receiving, at an automated test augmentation system, a design model and model coverage gap information from a model-based development tool, translating the model coverage gap information into machine-readable mathematical test objective expressions, developing a set of test objective operators by translating the machine-readable mathematical test objective expressions, localizing target operators for the identified coverage gaps within the design model, attaching the test objective operators to target operators of the design model to create a test model, augmenting the test model by propagating test objectives at the target operators to a test node operator of the design model, and executing, by a test generator, the augmented test model to obtain the test cases to cover the coverage gaps and the causes for the model coverage gaps. A system for implementing the model-based design and a non-transitory computer readable medium are also disclosed.

Abstract: A computer-implemented system for generating test cases and/or test procedures to verify software having a nonlinear arithmetic constraint over a Real number range. The system includes a translator that receives, as input, software specification models for the software to be verified. The translator is configured to generate, as output, a plurality of SMT formulas that are semantically equivalent to the software specification models. The system includes an analytical engine pool that receives, as input, the plurality of SMT formulas from the translator and analyzes the plurality of SMT formulas, and generates, as output, test case data for each of the plurality of SMT formulas determined to be satisfiable. The system includes a post-processor that receives, as input, the test case data from the analytical engine pool and generates, as output, the test cases and/or test procedures for the software to be verified based on the test case data.

Abstract: A method for automated test case augmentation includes receiving, at an automated test augmentation system, a design model and model coverage gap information from a model-based development tool, translating the model coverage gap information into machine-readable mathematical test objective expressions, developing a set of test objective operators by translating the machine-readable mathematical test objective expressions, localizing target operators for the identified coverage gaps within the design model, attaching the test objective operators to target operators of the design model to create a test model, augmenting the test model by propagating test objectives at the target operators to a test node operator of the design model, and executing, by a test generator, the augmented test model to obtain the test cases to cover the coverage gaps and the causes for the model coverage gaps. A system for implementing the model-based design and a non-transitory computer readable medium are also disclosed.

Abstract: A method for model-based design of safety-critical software is disclosed. The method includes receiving natural-language software requirements, developing a specification model by implementing either semantic modeling or graphical modeling, applying formal requirements analysis to the specification model, auto generating requirements based and robustness test cases from the specification model, developing a design model based on the specification model, applying test cases to the design model, auto-generating source code using the design model, verifying the source code using both test cases and static analysis technology, and compiling executable object code from the verified source code. If a result of the analysis of the software specification or design models is not satisfactory then adjusting the specification or design model to correct any inconsistency, and repeating applying the analysis and test cases.

Abstract: A linear actuator system including a cylinder, a piston slidably received within the cylinder and defining a piston chamber and a rod chamber in the cylinder, wherein the piston includes a plurality of orifices therethrough that place the piston chamber and the rod chamber in fluid communication, and a sealing member movable between a closed position, wherein the sealing member restricts fluid flow through at least one of the plurality of orifices, and an open position, wherein the sealing member is less restrictive of fluid flow through the orifices. The plurality of orifices may include an always-open orifice that is not blocked by the sealing member when the sealing member is in the closed position.

Abstract: An improved cold temperature compensation control method for an EH braking system in which cold temperature operation is detected without requiring a temperature sensor. An electronic controller monitors the pressure developed by one or more electrically operated boost units for a characteristic pressure profile that occurs in cold temperature operation of the braking system, and adjusts the control strategy when the characteristic pressure profile is detected. The characteristic pressure profile is deemed by its frequency and amplitude parameters; specifically, a frequency above a threshold frequency, and an amplitude above a threshold amplitude. In a first mechanization, the controller responds to a detected cold temperature operation by reducing the gain of a closed-loop pressure control, while in a second mechanization, the controller responds by switching from the closed-loop pressure control to a closed-loop position control.

Abstract: A control method for a manual back-up electro-hydraulic braking system in which the rear service brakes of the vehicle are intentionally operated in a manual back-up mode under specified non-failure operating conditions to conserve electrical energy. The manual back-up mode for the rear service brakes is initiated if braking is commenced while the vehicle speed is below a near-zero threshold speed. If braking is commenced above the threshold speed, the manual back-up mode for the rear service brakes is initiated when the vehicle speed falls below the threshold and the pressure command for the rear brakes has been substantially constant for at least a predetermined time. In this case, the rear manual back-up mode is initiated by reducing the rear brake pressure command to the rear boost units at a controlled rate until the rear brake pressure reaches the manually developed pressure, and then entering the manual back-up mode.

Abstract: A brake system control apparatus comprising: a sensor providing an output signal indicative of operator foot force on a brake pedal; an actuator coupled to wheel brake and controlling a wheel brake force applied by the wheel brake responsive to a control signal; a controller coupled to the sensor and the actuator and including a differentiator (60) receiving the output signal and determining a rate of change of the operator foot force on the brake pedal, a comparator (62) for comparing the rate of change to a predetermined minimum, wherein a rate of change above the predetermined minimum indicates a quick application of brake pedal force by the vehicle driver, a brake gain adjuster (64) for increasing a gain of the brake system when the rate of change is above the predetermined minimum, a brake command generator (72, 74) determining a control signal in response to the increased gain when the rate of change of brake force is above the predetermined minimum and responsive to a base gain when the rate of change