Purchasing an Inertial Measurement Unit, more commonly referred to as an IMU sensor, can be a tricky process. Because the price range and capabilities of these autonomous devices can vary so widely, it is easy to overspend on IMUs that may not be suited to your specific set of needs. At Inertial Sense, we offer practical help for our customers to ensure that you do not waste your money on an Inertial Measurement Unit that is not best suited to your needs. Here are a few key questions to keep in mind when planning your purchase of these advanced devices.


What Are You Trying to Accomplish With Your IMU Sensor?

Before you or anyone on your team purchases an IMU sensor, it is important to achieve a degree of clarity about what you are trying to accomplish. In many cases, IMU sensors may not be the best solution for your needs. Instead, you may require an Inertial Navigation System (INS) or an Attitude Heading Reference System (AHRS). About 50 percent of our customers begin the buying process without a clear idea of what they need. Purchasing an Inertial Measurement Unit when an INS or AHRS is actually necessary is a good way to waste money on an item that will never perform as required.


What Type of IMU Sensors Are Available?

Understanding the differences between an Inertial Measurement Unit, an Inertial Navigation System and an Attitude Heading Reference System can help you to determine the most appropriate choice for your project:

Inertial Measurement Units consist of three or more gyros and three or more accelerometers. Magnetometers may also be included in these devices. An IMU sensor is useful in providing information about the velocity, orientation, attitude, and rotation speed of autonomous devices. It produces raw data that must be compiled and interpreted before this information can be used. Your IMU sensor cannot generally serve as a stand-alone autonomous device without the addition of GPS and other sensors.

Attitude Heading Reference Systems incorporate GPS technologies along with the capabilities of an IMU sensor. A Kalman filter is generally required to produce output for your autonomous devices.

Inertial Navigation Systems combine all the capabilities of IMU and AHRS systems, including a Kalman filter, sensor fusion, and GPS to provide navigational data and output to systems that operate autonomously.

Choosing the most appropriate of these options will save you time, effort, and money on the purchase of these key elements in an autonomous navigation system. This can help you to avoid losing money unnecessarily when buying an IMU sensor for your project.


What Are Your Device’s Performance Needs?

Determining the precise performance specifications for your device is the next step in choosing the right Inertial Measurement Unit for your needs. This generally requires some careful consideration on your part and some assistance from experts in the inertial sensor marketplace.

What works in a smartphone is unlikely to perform as needed in an autonomous robotic system or a deep space telescope. Erring on the side of caution and investing in slightly more accuracy and capability than you think you will need is much better than lacking the necessary capability once your device is implemented.

One sure way to lose money when buying an IMU sensor is to opt for the absolute state-of-the-art when that degree of accuracy is not required for your project. Investing in lower-cost sensors and pairing them with other sensors and devices can often achieve the desired results at a much lower cost than top-end IMUs. This can also allow for greater customization of your device during initial setup and in the future.

The various components of your autonomous system must be combined in a way that ensures the highest level of data integrity and interoperability. Purchasing low-cost IMU sensors, GPS systems, magnetometers, and software systems and expecting them to work together seamlessly is not practical. You will need Kalman filtering software and other components to ensure the highest degree of data accuracy and the most reliable results.

Calibration and data filtering are critical elements in achieving the required results from your autonomous devices. Our proprietary sensor fusion solution is an ideal way to ensure that your IMUs work effectively for your purposes.

Relying on the filtering offered by sensor manufacturers is a hit-or-miss proposition at best. Working with a company that delivers the integrated inertial sensors, software, and devices necessary to achieve your goals is a far better option for most modern electronics and technology companies.


What Are Your Preferred Interfacing and Communications Protocols?

Few things in the engineering field are more frustrating than discovering that your expensive and well-researched IMU sensor will not communicate with the rest of your autonomous system. Differing sensors and components will use different interfacing protocols, especially if taken from several manufacturers. Working with a company that specializes in these types of sensors is usually the best way to manage these issues in a proactive manner. This helpful table can provide you with the basics on what communications protocols are used by each of our inertial measurement units and sensors.


How Many Do You Need and When Do You Need Them?

Establishing a timeline for your IMU requirements and the total number of IMUs you will require can help you to manage costs more effectively. As with most products, purchasing in bulk can often help you to reduce the cost-per-unit for these items. We can work with you to find the most cost-effective solutions for your projects and your sensor requirements now and in the future.

At Inertial Sense, we work with you and your company to ensure that you receive integrated and practical solutions for all your inertial sensor requirements. We have the experience and the expertise you need. If you wish to avoid losing money when buying an IMU sensor, we can provide you with the right solutions for your current and future projects. We are here to serve you.


Learn More

What’s The Difference Between GPS and GPS INS?

You Must Be Good at Sensors Before You Take On Autonomy

What Is a Calibrated IMU and Who Should Get One?