# System Trade Study Matrix for Component Selection

### Introduction

In any engineering project, selecting the right components is crucial. A System Trade Study Matrix offers a systematic approach to making informed decisions based on multiple evaluation criteria. This article explores what a System Trade Study Matrix is, why it's important, and how to construct one.

### What is a System Trade Study Matrix?

A System Trade Study Matrix is a tabular representation that helps in evaluating different components based on various metrics or criteria. It is particularly useful when the selection involves multiple conflicting requirements.

### Diagram 1: Basic Structure of a System Trade Study Matrix

|  Criteria 1  |  Criteria 2  |  ...  |  Criteria n  |

---------------------------------------------------------------------

Component A   |      ...     |      ...     |  ...  |      ...     |

Component B   |      ...     |      ...     |  ...  |      ...     |

.       |      ...     |      ...     |  ...  |      ...     |

.       |      ...     |      ...     |  ...  |      ...     |

.       |      ...     |      ...     |  ...  |      ...     |

Component Z   |      ...     |      ...     |  ...  |      ...     |

### How to Construct a System Trade Study Matrix

Step 1: Identify Components

List down all the potential components that can be used in the system.

Step 2: Determine Evaluation Criteria

Identify the metrics or criteria based on which the components will be evaluated. These can include cost, performance, reliability, etc.

Step 3: Assign Weights to Criteria

Not all criteria are equally important. Assign weights to them according to their relevance in your project.

Step 4: Evaluate Components

For each component, give a score based on each criterion.

Step 5: Calculate Weighted Scores

Multiply the score of each criterion by its weight and sum these up for each component.

Diagram 2: Weighted System Trade Study Matrix

| Criteria 1 (w1) | Criteria 2 (w2) |  ...  | Criteria n (wn) | Total Score |

------------------------------------------------------------------------------------------------

Component A   |       ...       |       ...       |  ...  |       ...       |     ...     |

Component B   |       ...       |       ...       |  ...  |       ...       |     ...     |

.       |       ...       |       ...       |  ...  |       ...       |     ...     |

.       |       ...       |       ...       |  ...  |       ...       |     ...     |

.       |       ...       |       ...       |  ...  |       ...       |     ...     |

Component Z   |       ...       |       ...       |  ...  |       ...       |     ...     |

### Practical Example on Selecting low-power MCU for IOT device

We are still tasked with selecting a microcontroller for a low-power IoT device. This time, we'll consider not only the technical specifications but also project management factors such as schedule risk.

### Assigning Weights

For this example, let's use the following weights:

Here's how our initial matrix might look:

|   Cost   | Power Consumption |   Area   | Schedule Risk |  Speed  |

------------------------------------------------------------------------------------------

MCU Option A  |    7     |        9          |    6     |       5       |    8    |

MCU Option B  |    5     |        8          |    9     |       7       |    7    |

MCU Option C  |    6     |        7          |    8     |       8       |    9    |

### Calculating Weighted Scores

To calculate the weighted scores, we'll multiply each score by its respective weight:

| Cost (0.25) | Power (0.25) | Area (0.15) | Risk (0.15) | Speed (0.2) | Total Score |

----------------------------------------------------------------------------------------------------------

MCU Option A  |    1.75     |     2.25      |    0.9      |     0.75    |    1.6      |     7.25    |

MCU Option B  |    1.25     |     2.0       |    1.35     |     1.05    |    1.4      |     7.05    |

MCU Option C  |    1.5      |     1.75      |    1.2      |     1.2     |    1.8      |     7.45    |

### Conclusion and Selection

Upon evaluating the weighted scores, we choose MCU Option C because for it is best suitable for realtime and low power IOT device.  However MCU Option A has slightly lower scores, additional factors such as vendor relationships or future scalability could be considered for the final decision.

### Summary and Conclusion

The System Trade Study Matrix stands as an essential framework for making informed decisions, offering a balanced perspective that is crucial for anyone involved in complex engineering projects.