The Role of Inertial Navigation System in Medical Engineering

doctor conducting tests in a laboratory

In the past, the inertial navigation system (INS) used to be the champion in the military, aeronautic, marine, land, and space navigation fields. With its ability to calculate positions, it proved a vital navigational solution for the said industries.

Now, INS is not only exclusively used in the abovementioned fields. With technological advancements, this navigational system branched out to other industries today. Medical engineering is one of them.

Medical engineering has found INS to be an effective tool to aid with various equipment in the healthcare sector. It plays a crucial part in saving lives, and to understand its role, let’s find out what is INS and how it works.

What is the Inertial Navigation System?

Inertial Navigation Systems are navigational systems that can calculate position using at least three gyros and three accelerometers. INS measures changes in relative motion to project a changing position. In simpler terms, it calculates your position based on where you came from.

Still confused? Let’s compare it with another navigation device that you’re probably more familiar with.


In the global positioning system, you get an absolute position after switching on the GPS receiver. Although not perfectly accurate, the GPS device can tell you your latitude and longitude to determine where you are on Earth. But in INS, it’s different.

In INS, you won’t know your position right after turning on the device. This is because INS measurement is relative to your last known position. This means you need to move from your current location to another for the system to work. Once you move, the device would then calculate where it is now, based on its own measurement.

Although INS is not as accurate as GPS, several testing methods like an INS simulator improves its performance. This simulation ensures usability in the field and reusability for repeat testing, allowing the inertial navigation system to offer better performance.

Applications of INS in Medical Equipment

medical surgeryNow that you understand the basic concept of the inertial navigation system, it’s time to learn its applications in medical engineering. Since determining the velocity, position, and attitude is important for most medical devices, INS plays a crucial role in developing various medical equipment.

In a study published by S.V. Ghasemzade and F. Jamshidi in 2018, INS was proven to aid various medical equipment, granting precise and fast positioning as well as attitude determination. It also provides a high-efficiency system for specifying position and attitude.

Below are some of the various medical equipment that relies on INS.

  • Synthetic gloves

Inertial navigation algorithms are programmed in synthetic gloves to determine position, velocity, and attitude. This allows synthetic gloves to measure accelerations and angular velocities, which are important for medical equipment that simulates hand gestures.

  • Endoscopic system

Inertial navigation also helps stabilize the image in endoscopic surgery. In this system, it uses one accelerometer and two gyroscopes to guide and navigate inside the human body. This gives surgeons control over the endoscopic device.

  • Controllable wheelchair

Inertial navigation is also used in controlling motions of a wheelchair. In this equipment, accelerometers are installed on a hat which is placed on a disabled person’s head. Patients with spinal cord injury can only move their head, and with the help of the hat, it can detect their motion. The hat then sends commands to a servo motor, controlling the motions of the wheelchair.

These are only a few of the various medical equipment where inertial navigation is being used. Other healthcare tools include angiography equipment, surgical robots, intelligent patient beds, and MRI devices.

With these applications, it is apparent how inertial navigation systems play a critical role in the field of medical engineering. And as technology advances, expect more applications featuring inertial navigation to be developed in the future.