Augmented and virtual reality applications must monitor the locations close to the user’s head, hands, or other control devices. Although there are several ways to track these motions, one of the most reliable is the use of electromagnetic motion tracking. The sensors utilize 3D cube geometries with three separate coils oriented in the X, Y, and Z axes.
When these coils are made, it is important to keep in mind that at present, applications require more precision than ever, and the speed of growth in this highly competitive market necessitates quick product development.
The AR/VR software that transforms the data from the sensors into virtual movement requires predictable, accurate data from all the coils. Roshan Shrestha, TT Electronics Design Engineer, says that product developers typically stipulate the size constraints, inductance (L), and direct current resistance (DCR) for every coil, leaving the actual design of the coil to the engineers.
Before manufacturing commences, the engineers at TT Electronics design and build prototypes using production materials for the developer’s assessment testing. The challenge is to choose from the full range of coil variables—winding angle, core material, wire gauge, number of turns, etc.—that allow the software and sensor to satisfy the requirements of the product developer in the best possible way.
So far, this process of hand calculation and trial-and-error testing was susceptible to error and labor-intensive. It was iterative and laborious, and only functioned because tolerances were usually looser than existing values. TT Electronics employs robust ANSYS Maxwell field simulation software for the examination of electromagnetic devices to realize present-day’s tighter tolerances.
A design engineer in Maxwell creates a 3D model of the cube (winding and core). The engineer establishes vital coil input variable information such as excitation to the coils and material features, and then starts the simulation to verify whether the coil factors are within specification and predicted performance.
Virtual prototypes that satisfy those stipulations are manufactured by the 3D simulation software. Based on the complexity of the design, results are obtained within minutes or hours. The virtual prototypes comprise all of the winding properties and material of an actual physical prototype and can be instantly tested in a simulated field without the need to develop a physical coil.
A physical sample can be developed using 3D printing for rapid assessment in the lab. In certain cases, several designs may be tested before developing the first physical prototype. The process is a lot quicker and more accurate than manual calculation and allows easy testing of parameters such as winding angle to obtain the ideal fit for the application.
Scott Cameron, Business Development Manager, says that the physical prototype is put to test by TT Electronics as well as its customers. The customers typically test the coil in prototype circuitry for the end product, which in certain cases can give rise to alterations to the coil specifications by the application developers. However, in many instances, the amount of alterations needed to create an ideal coil is cut along with cost and time to market.
The ANSYS Maxwell software and 3D printing are just a few of the tools TT Electronics utilizes to develop electromagnetic products that satisfy expectations.
This information has been sourced, reviewed and adapted from materials provided by TT Electronics plc.
For more information on this source, please visit TT Electronics plc.