3D Gestures for the Internet of Things



True single-chip gesture detection has arrived to the IoT. What’s the secret to leveraging this advanced technology for industrial, smart energy, medical, gaming and other applications?

Internet of Things (IoT) devices not only feature the latest in communication technologies and cloud connectivity, but are also reimagining century-old products such as light switches. IoT often brings additional functionality way beyond what was possible a few years ago. For example, the same light switch can now turn off all the lights in a home when you go to sleep, adjust the color and brightness of any light in the house, set an automated sequence of lighting scenarios and control all of that from a smartphone, regardless of whether you are at home. However, IoT devices are also embedded products, meaning that users expect to operate and control them without first reading a manual.

The Challenges and Opportunities

The user interface (UI) is a key element that can benefit the user—triggered by IoT but not limited to connectivity. Customer expectations for the UI are rising and, especially for embedded devices, come with power, cost and size restrictions. It can be a real challenge to bridge the user’s expectations of a modern UI with these embedded requirements, but solving this challenge can also be a critical factor in a product’s success. What does the 21st century light switch look like, and how can we leverage IoT beyond “everything is connected”?

Gestures, or meaningful hand movements, are a fundamental method of communication that has been used since the dawn of man, and are part of our everyday life. We “flip the lights on” with an upward movement, and we “make the lights brighter” with a simple clockwise rotation. Dimming or turning the lights off doesn’t require further explanation; gesture-based user interfaces are intuitive. Using gestures for control will spark a multitude of enhancements in consumer usability, as well as industrial design, and they can be done while keeping the project on budget.

f1
Figure 1: GestIC® technology utilizes an electrical field to detect hand movements.
f2
Figure 2: Gestures are detected when a hand disturbs the electrical field.

Using Electrical Fields

Microchip’s MGC3030/3130 gesture controllers enable the above scenarios, providing true single-chip gesture detection. These controllers are based on Microchip’s patented GestIC® technology, which uses an electrical field (E-field) to detect movements of the human hand (see Figures 1 and 2).

GestIC technology is based on capacitive sensing—it uses the same physics as capacitive touch buttons or touch screens. The electrode design is straightforward, so experience in touch implementations can be transferred to 3D sensing. Also, the system doesn’t depend on lighting conditions, and needs neither lenses nor openings to operate. For example, a light switch could have a smooth surface with the gesture-detection board seamlessly integrated; or it could even be hidden behind the drywall, supporting and not disrupting the room’s interior design.

This technology is also designed from the ground up for embedded usage. The controllers are truly single-chip devices, with small footprints and all the necessary means to deliver robust results—even under challenging environmental conditions. Embedding gestures using GestIC technology is a plug-and-play exercise. The gesture controller auto calibrates for environmental changes and runs the gesture detection on board. No host computing is required, and the technology comes with auto wake/sleep functionality. The latter is not only a key element in meeting the system’s low-power requirements, but is also fundamentally important for the use case. Auto wake enables 24/7 gesture detection, which matches the always-on user interface we expect from a light switch. When your hand approaches the light switch, the auto wake is triggered and used to illuminate the switch area prior usage. This is a valuable feature, as light switches are often used in the dark.

f3
Figure 3: GestIC Topology Using the MGC3030 3D Gesture Controller

Sensing is done by generating an E-field through an Electrode constructed from any conductive material, such as a Printed Circuit Board (PCB). The built-in analog front end, as well as the firmware running on the 32-bit core, senses and processes any changes in the field caused by a user’s hand, in order to recognize gestures and provide X-Y-Z coordinates for the user’s hand. The built-in analog and digital noise filtering provide the basis for the robust gesture detection. Even dynamic, changing environments do not affect the system.

The whole family of controllers communicates via I2C™ to an optional host. Gestures are communicated to the host, and this simple topology (see Figure 3) enables fast integration into any device.
The host requirements are minimal, and the Gesture Port also supports host-free usage. With the Gesture Port feature, specific gestures are simply mapped to configurable Input/Outputs. This enables gesture-based user interfaces without any SW effort at all during product development, thus shortening time to market. Designing in GestIC technology is done via a graphical user interface (GUI), to tailor the behavior, select the gestures in use, and communicate settings and timing to the application.

The feature set of the GestIC controllers covers 3D gestures as well as touch and proximity detection. Real-time, free-space motion tracking can be added, with the X-Y-Z coordinates reported.

f4
Figure 4: MGC3030 3D Gesture Controller

Conclusion

GestIC technology offers a versatile portfolio of gestures. The benefits of this UI approach are evident in a broad range of home-automation applications, such as interior lighting, audio, heating, air conditioning, windows, shutters and
sun-protection systems, but are by no means limited to these use cases. The ability to detect casually performed gestures can also help reduce driver distraction in cars, for functions such as answering/declining phone calls. A simple movement of your hand can advance music to the next track on your wireless speaker, while a rotation can adjust the volume. But we’ll know that the age of embedded gesture sensing has truly arrived when we can choose to flush a toilet without touching anything (unlike the current, inaccurate flush sensors that merely detect movement).
Andreas Guete is the global marketing manager for Microchip’s Human Machine Interface Division. He is responsible for marketing Microchip’s advanced input solutions, particularly the GestIC 3D and free space gesture tracking and recognition technology.



Andreas Guete is the global marketing manager for Microchip’s Human Machine Interface Division. He is responsible for marketing Microchip’s advanced input solutions, particularly the GestIC 3D and free space gesture tracking and recognition technology.

Guete has worked in the electronics industry for 12 years. He joined Microchip in 2012 with the acquisition of IDENT Technology, where he held the role of Director Technical Sales, Asia. He originally joined IDENT in 2005 as a project manager.

Guete holds Masters degrees in Industrial Economics and Business Engineering from the University of Ilmenau in Germany. He has also registered a number of patents in the field of touch and proximity sensors.

Note: GestIC is a registered trademark of Microchip Technology Incorporated in the U.S.A. and other countries. All other trademarks mentioned herein are the property of their respective companies.

Share and Enjoy:
  • Digg
  • Sphinn
  • del.icio.us
  • Facebook
  • Mixx
  • Google
  • TwitThis

Tags: ,