Dependability number

An apparatus for providing an optimal system configuration out of a plurality of candidate system configurations j, the apparatus comprising:

• a computing device with an input interface, a processor, a memory and an output interface,
• wherein the computing device is configured to perform a component fault tree analysis with a corresponding Reliability, Availability, Maintainability and Safety (RAMS) analysis for each of a plurality of candidate systems configurations j;
• wherein the input interface is configured to receive an input signal comprising data indicating the plurality of candidate system configurations j, wherein the received data includes a plurality of actual values associated with a plurality of dependable properties i obtained by the component fault tree analysis with the corresponding RAMS analysis for each of the plurality of candidate systems configurations j;
• wherein the computing device is configured to determine expected or reference values for each of the plurality of parameters;
• wherein the computing device is configured to compare the plurality of actual values with the expected or reference values for each of the plurality of dependable properties i for each of the plurality of candidate systems j;
• wherein the computing device is configured to implement a dependability metric module and an optimizing module;
• wherein the dependability metric module is configured to determine at least one quantitative dependability metric value for each of the plurality of candidate system configurations j,
• wherein the at least one quantitative dependability metric value for each of the plurality of candidate system configurations j is based on
• a) determining a dependability property fulfilment value Xij for each of the plurality of dependability properties i for each individual candidate system configuration j, wherein the dependability property fulfilment value Xij depends from the comparing the plurality of actual values with the expected or reference values for each of the plurality of dependable properties i for each of the plurality of candidate systems j;
• and further based on
• b) weighing the dependability property fulfilment value Xij for each of the plurality of dependability properties i using a dependability property weighting factor Ki for each of the list of dependability properties i for all of the plurality of candidate system configurations j;
• wherein the optimizing module is configured to determine an optimal system configuration out of the plurality of candidate system configurations j based on a quantitative comparison between the at least one quantitative dependability metric value for each of the plurality of candidate system configurations j;
• wherein the output interface is configured to output an output signal indicating the determined optimal system configuration;
• and
• a producing machine, wherein the output signal and the producing machine are configured such that the producing machine is controlled by the output signal to produce a system having the determined optimal system configuration.