“Medical infusion pumps and syringe pumps not only improve the efficiency, flexibility and reliability of clinical drug delivery operations, but also reduce the workload of nursing care and reduce doctor-patient disputes. At present, most of the infusion pumps/syringe pumps on the market use stepper motor solutions, so what are the advantages of the servo solution compared to the stepper solution? Take a look.
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Introduction to this article
Medical infusion pumps and syringe pumps not only improve the efficiency, flexibility and reliability of clinical drug delivery operations, but also reduce the workload of nursing care and reduce doctor-patient disputes. At present, most of the infusion pumps/syringe pumps on the market use stepper motor solutions, so what are the advantages of the servo solution compared to the stepper solution? Take a look.
Application Background Science of Infusion Pump and Syringe Pump
In some clinical situations, accurate doses are required, so ordinary drug delivery methods are definitely not feasible, especially for critically ill patients such as ICU, CCU, pediatrics, cardiothoracic, brain surgery, general surgery, etc., the dose may be more or less. It affects the patient, and the speed at which the drug enters the patient’s body may also affect the patient, so there is a need for a product that can control the amount of the drug and the speed at which the drug enters the patient’s body.
Medical syringe pumps are such a product. Generally, infusion pumps are used when high precision and strict control of drugs are required. The role of medical infusion pumps is not only for patients, but also for medical staff. Under normal circumstances, if medical staff are required to grasp the patient’s medicines, there will definitely be a gap, and this gap may be affected by many factors. The use of medical syringe pumps is also a liberation for medical staff.
The existence of medical infusion pumps improves the efficiency and flexibility of clinical drug delivery operations, reduces the workload of nursing, and reduces doctor-patient disputes, which is not only good for patients, but also for medical staff.
The medical syringe pump solution is composed of a stepper/servo motor and its driver, a screw rod and a bracket, etc., with a reciprocating screw and a nut, so it is also called a screw pump. The nut is connected with the piston of the syringe, and the liquid medicine is contained in the syringe to achieve high-precision, smooth and pulsation-free liquid transmission. When working, the stepper/servo motor drives the screw to turn the rotary motion into a linear motion, and pushes the piston of the syringe for injection and infusion. The injection speed can be set by the operator through keyboard operation, as shown in the following figure:
Stepper Motor VS Servo Motor
So, choose a stepper motor or a servo motor as the control scheme for the infusion pump/syringe pump? Don’t worry, let’s compare the characteristics of the two motors first, and then make a choice after understanding the characteristics of the two motors. The following table shows the comparison of the two motors:
The above table compares from various aspects. It can be seen that compared with stepper motors, servo motors have certain advantages in overload capacity, control characteristics, torque characteristics, response speed, low frequency characteristics, temperature rise characteristics and anti-interference.
Especially when taking medicine, when the speed of the stepping motor is fast, the torque is usually not enough, resulting in a slow medicine taking speed. Usually, the medicine taking time is more than 8S, which has become a pain point in the industry, and the servo motor is rated torque within the rated speed, not only The low-speed characteristics are good, and the speed range is wider, which can perfectly solve the pain points of the stepping solution.
Servo control ESC block diagram
The following is the block diagram of the infusion pump/syringe pump servo control ESC scheme launched by Ligong Technology. The position, speed and torque are controlled by closed loop, which has the advantages of high control accuracy, fast response speed, strong anti-overload capability, stable and reliable operation, and basically no temperature. It has the advantages of high power and noise, stable injection and bidirectional operation, supports fault monitoring, and has high energy consumption utilization. The software adopts AMetal-FOC motor-specific algorithm, which has strong versatility and can be easily adapted to various motors.
Servo Control Demo
The video below shows the evaluation board to achieve precise control of the speed and position of the servo motor to meet the requirements of scenes such as stable injection and bidirectional operation. If you are still using the stepper motor solution, want to optimize and improve the original solution, or are making similar products, you may wish to contact us and take a look at this servo motor solution.
The Links: LQ084S3LG03 CM200TXPA-24T