Ch1_BME520_Introduction_System_Engineering_updated.pdf

Biomedical Devices Design and Troubleshooting (BME520 ) Chapter 1: Introduction Claudio Becchetti, 1th Edition Dr. Qasem Qananwah 7/27/2024...

Biomedical Devices Design and Troubleshooting (BME520 ) Chapter 1: Introduction Claudio Becchetti, 1th Edition Dr. Qasem Qananwah 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 1  Chapter 1: Introduction Concepts Design is not research A design task may require research to accomplish a task, but it typically involves the integration of knowledge, rather than the generation of knowledge. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 2  Chapter 1: Introduction Concepts WHAT MIGHT BE DESIGNED? Biomedical devices Modified patient brace for an individual Patient (e.g., Alzheimer’s) (or pet) tracking device Development of a hand exerciser Improved safety warning system for an intensive care unit Improved patient monitoring for premature infants Development of a surgical tool for use in spina bifida surgery Development of an adjustable tray for a spinal cord-injured patient 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 3  Chapter 1: Introduction Concepts Less than one-third of medical device development projects succeed in getting to the marketing stage (Kelleher, 2003) 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 4  Chapter 1: Introduction Concepts Table 1 Problems, solutions and tools in medical design Reasons according to (Kelleher, 2003) Main engineering approaches 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 5  Chapter 1: Introduction Concepts The application of engineering methods and processes may significantly reduce the risk of failures, and the design will success 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 6  Chapter 1: Introduction Engineering Approaches Engineering methods and processes (Engineering approach goes through the following logical sequence) 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 7  Chapter 1: Introduction Problem Formulation Problem formulation: is the set of inputs and constraints available for a problem solution. A systematic approach to defining a problem helps greatly in solving the problem itself 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 8  Chapter 1: Introduction Problem Formulation Figure : The problem framework 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 9  Chapter 1: Introduction Design Process 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 10  Chapter 1: Introduction Design Process 1. Recognizing the Need for a Product or Service Design process goes 2. Problem Definition and through the following Understanding logical sequence 3. Research and Preparation 4. Conceptualization 5. Synthesis 6. Evaluation 7. Optimization Figure: A generalized flowchart for the design process. 8. Presentation 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 12  Chapter 1: Introduction Design Process The design step is the process of developing a set of specifications that explains how the product is implemented in response to requirements 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 13  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) A. Concept: should outline briefly the scope and the content of the project. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 14  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) B. Requirement analysis defines what the product must do according to customer/buyer needs. A requirement should have these attributes: 1. It is feasible and it can be verified through inspection, demonstration, test or analysis. 2. It must not conflict with other requirements. 3. It can be translated into a technically and economically feasible design specification. 4. It is mandatory and it identifies a real business need/opportunity. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 15  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) An example of requirements on an ECG may be: Req 1.1 The ECG shall be able to display differential voltages of +/- 5 mV. Req 1.2 A 20µV peak-to-peak sinusoidal signal shall yield a visible ECG trace 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 16  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) C. The design specifications are performed by developers, who are expert in implementation also referred to as the ‘solutions domain’. A typical specification in response to the previous requirements is Req 1.1 The ECG shall be able to display differential voltages of +/- 5 mV. → Spec. 1.1 the ECG A/D converter shall have at least 10-bit real resolution 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 17  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) D. performance evaluation stage: using proper tools (e.g., CAD – computer aided design) that allow the evaluation of electronic, mechanical, thermal and radiation behavior through high quality simulations. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 18  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) E. Implementation can take place at various levels of complexity using demonstrators, prototypes and the final sample products. All the components (software, hardware, mechanical objects, sensors) are then integrated within the system. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 19  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) F. Test that will include validation of all requirements, and verifications of the functions of the product with clinical trials usually being required by certification. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 20  Chapter 1: Introduction Design Process Product Development Life Cycle (Waterfall Model) System decomposition is required because the system itself is generally too complex to be handled as a single unit (i.e. Divide and conquer approach). (Will Discuss Next: Section 1.5 ) The life cycle waterfall model considers a sequential development strategy where each stage starts at the end of the previous: first planning, then requirement analysis, design and so on. Unfortunately, this model is critical because in innovative projects like new product design, some details only become clear at the later stages of implementation. (Will Discuss Later: Section 1.6). 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 21  Chapter 1: Introduction System-Subsystem Decomposition Any design of non-trivial products has a high level of complexity given by the set of design details that have to be addressed and solved coherently. Use Roman strategy which can be summarized by the phrase ‘divide and conquer’ Therefore, dividing systems into subsystems make life easy 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 24  Chapter 1: Introduction System-Subsystem Decomposition Example: Dividing systems into subsystems Medical instrument system diagram. Medical instrument subsystem decomposition. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 25  Chapter 1: Introduction System-Subsystem Decomposition The project team can then address in parallel the activities, and at the end of subsystem implementation, an integration/testing step will yield the overall product. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 26  Chapter 1: Introduction System-Subsystem Decomposition System Benefits of system-subsystem decomposition: System design less complexity and then lower associated costs, lower risks and lower development time may be 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 27  Chapter 1: Introduction System-Subsystem Decomposition System-subsystem decomposition process can be implemented as follows: 1. At the first level define actors, interfaces and systems with a limited detail level 2. create a second level by decomposing the system into subsystems and interfaces 3. create additional levels iteratively by decomposing subsystems from the previous level 4. define other levels until the level of detail is satisfactory 5. check coherence among levels, analyzing the corresponding interfaces and subsystems. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 28  Chapter 1: Introduction The business Context for design The reasons for product design failure 1. product development outside the market needs 2. product development is too late to exploit windows of opportunity. products should be market-driven 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 29  Chapter 1: Introduction The business Context for design A first question that the business plan must respond to is: “ Why should customers buy our product and not those of our competitors?” ➔ ‘differential competitive advantage’ The key element is the ‘perceived performance’: 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 30  Chapter 1: Introduction The business Context for design Performance, cost and price are strictly related. Business Terms: ‘product marginal cost’: an increase of the production cost of the equipment due to the implementation of the specific feature. especially for features implemented in hardware. ‘feature investment’: is the additional investment required to develop the feature. Cost of ‘n’ products: PMC: Product Marginal Cost (i-th feature cost of raw material, labor, etc..), PIi: product investment required to develop i-th feature. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 31  Chapter 1: Introduction The business Context for design Gross profit versus number of product sold when a certain quantity of product has been sold (i.e., the break-even point), the business becomes profitable. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 32  Chapter 1: Introduction Project Management in Product Design The design of a medical product is a typical project activity; therefore, it is worth analyzing the major aspects and risks in managing projects. A discipline (project management) has been developed, in order to define rules, processes and best practices required to increase the probability of success. The success of a project has to be assessed over three axes: time, cost and performance. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 33  Chapter 1: Introduction Project Management in Product Design Example: According to IT managers (Bull Survey, 1998), IT projects fail because of Delay (75%) Excess costs (55%) Non-achievement of planned performance with a proper level of quality (37%). 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 34  Chapter 1: Introduction Project Management in Product Design Risk management is a critical aspect that is sometimes underestimated in projects. In medical design, risk management is compulsory to ensure patients’ and users’ safety. Unexpected risk occurrence is a major reason for project failure. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 35  Chapter 1: Introduction Project Management in Product Design In risk management: it is important that 1. risks are identified and monitored throughout the project 2. the probability (Pi) of each risk is assessed 3. the economic cost (Ci) impact and technical consequence of the risk is evaluated. 4. an estimated extra cost CTot due to the risks is assessed. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 36  Chapter 1: Introduction Project Management in Product Design In risk management: it is important that Example: 5. actions are taken to reduce most impacting risks 6. an extra budget for risk management (e.g., Extra Budget > CTot) must be set aside 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 37  Chapter 1: Introduction Project Management in Product Design Figure : Achieved Performance behavior vs. time. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 38  Chapter 1: Introduction Project Management in Product Design Additional time is required by the team to achieve the background know-how. This time lag is generally inversely proportional to the experience of the task. The effort required to become expert in a specific type of project/technology is inversely proportional to the experience already gained in similar projects/technologies. Learning Curve 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 39  Chapter 1: Introduction Intellectual Property Rights and Reuse know-how is used to reduce the cost, risk and development time of the product to be designed. The know-how may concern hardware schemes, algorithms, industrial design, man-machine interfaces, trademarks, copyrighted material or software/firmware code. Some of these elements may be patented, others may be used only under specific conditions expressed in the associated licenses. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 40  Chapter 1: Introduction Intellectual Property Rights and Reuse Main patents are: 1) international patents, permits ‘reserving’ of patents almost worldwide 2) US patents, 3) EU patents. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 41  Chapter 1: Introduction Intellectual Property Rights and Reuse A patent is a set of exclusive rights granted by some countries to protect an invention, that is, something new, useful and non- obvious. Patent investigation is nowadays quite simple using the Internet. 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 42  Questions ???? 7/27/2024 BME520: Biomedical Devices Design and Troubleshooting Biomedical Systems and Informatics Engineering Department 43