跳至主要内容

How to Choose and integrate a medical device with stepper motor

Recently almost every medical device I design requires a stepper motor. After working with these motors so frequently, I’d like to share what I’ve learned about medical device stepper motors, the different types of stepper motor configurations, and how to drive stepper motors properly.
How to Choose and integrate a medical device with stepper motor
Stepper Motor Drive Configurations
Stepper motors typically come in two motor winding configurations. Before selecting which configuration is appropriate for your application, you should understand the basic difference between the two. This choice will be important when selecting how to drive the motor.
Pro Tip: You can use a unipolar motor as a bipolar motor if you ignore the center tap. This can come in handy if a particular design of motor is only available in a unipolar configuration.
How to Choose and integrate a medical device with stepper motor
Stepper Motor Drive Signals
Typically three types of drive signals are used to control the motion of a stepper motor. Each drive type increases in complexity, but adds additional features and options.
How to Choose and integrate a medical device with stepper motor
A wave drive only energizes one phase at a time. Wave drives are simple to implement with basic hardware, but are rarely used. Because only one coil is energized at a time, torque is significantly reduced.
Stepper Motor Drive Circuits
The most common methods for driving a stepper motor include a simple constant voltage or L/R (L refers to electrical inductance and R stands for electrical resistance) driver, a chopper drive, or a sine wave/micro-stepper driver.
Stepper Motor Integrated Drivers
Once a stepper motor hybrid has been selected to suit its mechanical requirements, the next thing is to get that motor turning. It is easier than ever to make a motor operational by selecting an off the shelf stepper motor driver IC or development board. Many of these boards provide features such as current feedback, built in acceleration profiles, and even onboard path planning for more complicated motion control.

评论

发表评论

此博客中的热门博文

Advantages and Disadvantages of Permanent Magnet Stepper Motor

A stepper motor is an electro-mechanical device that actuates a train of step movements of a shaft in response to a train of input pulses. The step movement may be angular or linear. The step movement of the motor is according to the input pulse. The performance of a stepper motor — both in terms of resolution (or step size), speed, and torque — is influenced by construction details, which at the same time may also affect how the motor can be controlled. As a matter of fact, not all stepper motors have the same internal structure (or construction), as there are different rotor and stator configurations. Advantages and Disadvantages of Stepper Motor The advantages of a permanent magnet stepper motor are It is compact and small in size, which makes it useful in many applications Due to the absence of any external excitation, the losses are less Due to the absence of any external excitation, the maintenance is less. It can be connected to the external circuit, to control the speed of the...
发表评论
阅读全文

How to Choose the Right Pancake Stepper Motors for Your Needs

A step motor is a type of electric motor that uses a series of electrical pulses to move the rotor. The rotating rotor causes a linear actuator, which produces motion in one direction. The pancake stepper motor is a type of step motor that has the capability to rotate continuously in both directions without any need for periodic rotary encoder. It is also known as the "pancake" stepper because it resembles a pancake, with its flat shape and circular cross-section. This article discusses how this type of step motors work and their applications in industrial machinery such as 3D printers, CNC machines, and robotics. What Makes the Pancake Stepping Motor Different From Others? The pancake stepping motor is a type of electric generator that uses an electromagnet to produce electricity. It is also known as the pancake motor because it looks like a pancake when it is folded in half. It has been around since the 1970s, but it saw a surge in popularity after the Fuk...
发表评论
阅读全文

Knowledge on stepper motors handle inertia mismatching

Inertia mismatch is the difference between the inertia of the system and inertia of the stepper motor. A large inertia mismatch is usually best avoided for machines run by stepper motors ( nema 17 gearbox or nema 23 planetary gearbox ). One, the stepper motor itself has inertia it must overcome, in addition to the inertia of the system it drives. Two, friction further affects inertia, and three, having too much torque from an oversized stepper motor poses its own set of problems. Inertia mismatch greatly affects how stepper motors operate. The motors cannot accelerate and decelerate rapidly with an extreme inertia mismatch. If they have sufficient torque, but an inertia mismatch is present, the load may not start or stop at the proper time or place. At its most extreme, inertia mismatch can cause skipped steps or non-functioning stepper motors … along with noise, vibration, and heat. There are a few ways to handle inertia mismatch. One is simply to size and match motor and loa...
发表评论
阅读全文