5.1 – Introduction

Introduction

Motors are very common in the biomedical world. They can be found in a variety of different equipment, including: Dialysis machines, Centrifuges, Medical Imaging (CT, fMRI), Pumps, blowers and compressors, Surgical tools such as saws and drills, Pumps – infusion, insulin,  Implantable devices (ventricular assist devices, pacemakers, defibrillators, nerve stimulators), Prostheses and many other items.

Many qualities can be attributed to motors and we will learn how these qualities are represented in different types of motors. Example of common qualities biomedical technologists look for in a motor:

• Efficient
• Quiet
• Reliable
• Produce no sparks during normal operation (arcless)
• High torque to dollar ratio (high power density)
• Precise
• High speed (surgical tools and centrifuges)

You will not be able to find all of these qualities in a single motor; therefore, we will learn how to choose the appropriate motor for the task at hand. For example, a surgical drill needs to be precise and high speed but being quiet is not necessarily required. Where motors in infusion pumps need to be quiet, reliable and precise but do not necessarily require high speed or high torque. We will end this week by discussing how to troubleshoot motors on the job site.