The Research And Development Of The VS Series Patient Monitor

Patient monitor is a medical instrument that is widely used in the medical environment. It is used to monitor the real-time vital signs of severe patient, such like ECG, Blood press, SpO2 and body temperature. When abnormal vital signs are monitored, the monitor will issue sound and light alarm so that doctors could save the patient's life in time.Philips Medical Systems is the leader of the global patient monitor market. In year 2004, the volume of the global patient monitor market is $2 billion. Philips positioned the No. 1 with 40% market share. But this is mainly contributed by the high-acuity monitor. In the field of the low-acuity monitoring, Philips only has 3 kinds of products that are out-sourced by other company. Both the market share and profit are minor. Further more, with the brought forwarded obsolete of one problem product, Philips'market share in this field shrunken more. To win the market, Philips founded the department of low acuity monitoring. The objective of this department is to develop Philips'own products in two years. This is just the subject of this thesis– the R & D of the VS series patient monitors.Being the leader of the mechanical team, my tasks in this project include architecture layout, recorder and sheet metal parts design, mechanical structure reliability analysis and test, system temperature field simulation and machine thermal profile test and adjustment.The most difficult points in this project are closely relative to the characteristics of medical instruments and the portable feature. Detail say are just small size, lightweight and high reliability. But amount of components inside of the machine are OEM made, we have no control to their size and weight. Further more,to insure the performance of the instrument we have to use some big and heavy components, such like big battery and big transformer. Small size means we need to make the best usage of space. But this may bring difficulty to the assembly process, cooling of the machine is also more difficult. At the same time, portable brings high requirement of shock and vibration proof to the machine. To solve these problems, we adopted the ideology of concurrent engineering, performed the DFX analysis concurrently with the structure design. Such as the dynamic assembly process simulation, temperature field simulation, and structure FEM analysis. Also experiment studies of machine thermal profile, shock and vibration had been conducted to prove the accomplishment the design task. Mainly they are in four details:1) Use the 3D solid body molding technology, simulate and optimize the product weight and assembly from the early phase of the design. This proved the product weight meets the requirement, assembly process easy and reasonable. At the same time, this way shortened the product development time and saved the cost.2) Simulate the system thermal character at the early phase of the design; Build the system temperate field with the ICEPAK software. Adjust the system architecture according to the analysis result. This made the components layout reasonable, kept the system temperature at proper level and avoided making big change to the system architecture at the late phase of the design.3) After the lab prototype had been finished, tested and adjusted the system thermal character with the'virtual instrument'tool; improved the user experience at the precondition of ensuring the system reliability.4) Performed the shock and vibration test to the production prototype, analysis the failure component with the finite element tool, adjusted and verified the component structure, ensured the reliability of the system mechanical performance.