How to Tell if 3D Sensing is Right for Your Application

3d sensingMachine vision is a major enabler of industrial automation technology. Traditionally, 2D imaging has been the primary machine vision technology in the industrial sector. Today, however, 3D sensing is solving some of the most difficult automation challenges and bringing a whole new level of capabilities to industrial automation.

3D sensing can be a powerful automation solution, but it’s not suited for all applications. Some processes will benefit from 2D vision instead. So how do you know if 3D sensing is right for your application?

Operating Parameters of 3D Sensing

It’s best to first take a look at the general operating parameters of 3D sensing and compare this with your own application. One major limitation in 3D imaging applications is depth of field, or extending the Z-axis.

Depending on the type of 3D imaging technology being used, depth of field can range anywhere from below 50 mm to 100 m. Different technologies have different operating ranges, but what they all have in common is that increasing the depth of field requires a shrinking of the aperture. This reduces the amount of light captured, which can lower image quality significantly.

Types of 3D Sensing Systems

Depth of field is a critical consideration, but so is the type of 3D imaging technology. There are several different types of 3D sensing systems out there.

  • Laser triangulation: one of the most common types of 3D sensing, laser triangulation works by projecting a laser onto a part or other surface. Depth is measured by the deformation of the laser, making this technology good for large depth of field applications.
  • Photogrammetry: a method of computing a 3D reconstruction based on a large number of 2D images of an object. Photogrammetry is a common alternative to LIDAR systems.
  • Stereo vision: this type of 3D imaging mimics the way humans perceive 3D images – two sensors are used at different angles to calculate and represent depth. Typically stereo vision is used for applications that don’t require measurements, such as counting people.
  • Structured light: with no need for moving parts, structured light 3D sensing systems are some of the most sophisticated solutions out there. They leverage an innovative projection technique to encode 3D information directly on the scene.
  • Time-of-flight: these systems detect the time of light travel between the light emitter, an inspected object, and back to the detector. Time-of-flight systems are either area sensing or LIDAR systems.

Deciding whether or not a 3D sensing system is right for your application is difficult. There are a number of 3D technologies, produced by an ever-expanding range of suppliers, all with different operational parameters and benefits. To start making this decision, it’s best to look at the requirements of your application and how these align with the technologies available.