Article by: Rigol Technologies
This article examines the testing analysis of high-frequency electric knives and breathing apparatus in the development stage.
Background and state of development of the medical electronics industry
With the aging of the world population, rising health care costs as well as the growing demand from emerging developing countries for medical diagnosis and treatment, the global demand for medical electronic products will increase. And by the recent economic development and the continued focus on improving the healthcare system for the whole society, the demand for the global medical electronics market is also showing a stage of rapid and stable development. .
This continuous demand has greatly boosted investment in the field of medical electronics, manufacturers of medical electronic equipment are constantly improving the technological level and developing innovative applications which promote stable development of the global medical electronics industry.
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On the current global constitution of medical electronic products, the products of US and European companies occupy a dominant position, followed by Japan on a number of professional projects also has certain advantages. The medical electronics industry in developing countries started late due to weak bases, their products are mainly concentrated in low-end products, and high-end equipment is heavily dependent on imports.
But with the rapid increase in R&D, as well as the market orientation from high-tech to universal, product competitiveness is gradually increased, there have been a number of core competitiveness enterprises with the benefit of digital medical imaging and in vitro diagnostics. With a high investment fund and a faster product cycle, how to improve test efficiency and reduce test development costs should also be considered at the product development stage.
Analysis of test technology
RIGOL can provide customers with comprehensive and cost-effective test and measurement instruments, which can meet the testing requirements of medical electronic equipment companies and reduce capital investment in the early stages of pre-research to speed up testing cycles. product development. Here we focused on the analysis of high frequency electric knife and respiratory machine testing at the development stage, to help you understand the testing application of RIGOL instrument products.
Product testing overview
High Frequency Electric Knife Test Analysis
The high frequency electric cautery knife (HF surgical device) replaces the electrosurgical instrument organized by mechanical cutting scalpel. Due to the high-frequency electric knife that can be cut and coagulated at the same time, in mechanical scalpel surgery difficult to access and implement (such as: abdominal pipeline ligation, prostate urethra tumor resection), it is universally applied. Due to its high precision, and therefore for the power waveform, voltage, current and other safety indicators require rigorous testing. The output power test can be calculated by using an oscilloscope to test the output terminal voltage and the output circuit current. The precision and correctness of the output power adjustment is fundamental to ensure the safety of the surgery, so that the precise degree of the output power adjusted by the high frequency electric knife can be accurately measured by a probe differential and an oscilloscope.
Figure 1: High frequency electric knife output power test.
In addition, some high frequency electric knife manufacturers have humanized and customized design. According to human tissue impedance monitoring and neurophysiological stimulation pattern to determine the different parts and pain, adjust the treatment mode. Thus, the testing process requires precise simulation of human body resistance and nerve signals to test whether coagulation can produce an accurate processing frequency signal mode. So you can use a high precision voltmeter test to simulate the impedance resistance and use a waveform generator to simulate a neural signal to test if the coagulation output mode is accurate.
Figure 2: Simulate the physiological stimulation mode.
Description of the fan test
In modern clinical medicine, the ventilator as an effective means of artificial replacement of the function of autonomous ventilation in the field of modern medical science occupies a very important place. Usually in the test, the pipeline will be built into a ventilation fan pressure transmitter, the working pressure when the fan passes gas from electrical output to an oscilloscope to display voltage waveform changes. After long monitoring, the conclusion that pressure limits access by the relationship between voltage and pressure, key parameters respiratory rate, minute ventilation, etc.
Figure 3: Fan stress test.
Introduction to portable mobile medical surveillance equipment communication test. With increasing internet coverage, an aging population, rising healthcare costs, remote monitoring and other new social conditions, this will allow medical devices to evolve towards portability and convenience. connectivity. The future mobile Internet health sector will enter a very rapid development phase.
Figure 4: Remote monitoring equipment communication test.
Figure 5: Wireless receiving end sensitivity and bit error rate test.
In the mobile Internet medical industry, the requirement of the medical device is not only to meet normal use, but also to meet stable communication. Wi-Fi, Bluetooth and other communication modules are becoming a key project in medical electronic equipment. Usually the test project uploaded the signal carrier frequency offset, transmit power, receive end signal sensitivity and bit error rate and other parameters. Usually, for the above indicators test, we can provide a test system including spectrum analyzer, RF signal source and oscilloscope for accurate and efficient testing.
Overview of the ECG test
The electrocardiograph is an instrument for recording the ECG. It can automatically record biological signals (ECG) produced by myocardial excitation of cardiac activity. It is a common medical electronic equipment for clinical diagnosis and research. Testing the ECG machine usually requires a mV level signal so that we can use an arbitrary waveform generator to generate a low amplitude ECG signal to test the instrument.
Figure 6: The arbitrary waveform generator generates a low amplitude ECG signal.
Image 7: Arbitrary waveform generator integrated with several arbitrary waveforms.
Electromagnetic compatibility pre-test of medical electronic products
With the development of medical electronic equipment technology, resulting in an increasingly complex electromagnetic compatibility environment, such as incorrect design of the EMC performance of medical devices, it is easy to cause equipment malfunction, loss control and failure, endangering the health of patients and medical personnel. .
Figure 8: Near field radiation test to determine the source of the interference device.
With more stringent EMC standards, all manufacturers of medical electronic equipment should think about electromagnetic radiation indicators at the research and design stage, or improve the product under the electromagnetic compatibility test at the inspection institute of medical devices to improve the product through the rate. Based on this, RIGOL can provide customers with spectrum analyzer with EMI filter and quasi-peak detector function, and is equipped with near-field probe to ensure electromagnetic radiation pre-test, it can accurately locate the source of interference and debug. All test results are generated automatically via software.