Nicholas W. Pinto, Suresh Gopalakrishnan, Chandra S. Namuduri, Nancy L. Johnson, and Mark Vann General Motors, Warren, MI

General Motors has invented a device that indicates when an unsafe level of energy remains in an electrical panel box after the main power has been disconnected. Possible sources of this energy may be incorrect wiring, external device add-ons, and the presence of residual charge from capacitors. The device works by engaging a safety latch mechanism built with shape memory alloy (SMA) technology along with an audio or visual alarm.

The SMA Secondary Safety Latch and Lock mechanism is engaged when the main power disconnect lever of the machine is pulled. When the mechanism is engaged, any charge on the power lines would conduct current and resistively heat the SMA actuator. The actuator contracts when heated, engaging the locking pin and making it impossible to open the panel door. This alerts the operator that energy still remains inside the box.

The SMA actuator and the indicator (for example, LED or buzzer) could also act as current loads and drain any capacitive residual charge. When the charge is removed or depleted, the SMA actuator cools and is reset by the biasing spring, unlatching the lock and indicating to the operator that the panel is safe to access. The system may also include an optional bypass mechanism so that the system can be serviced in special situations by trained individuals.

One unit can be used with a wide range of AC or DC voltage applications, and no external power is needed for operation. The SMA Secondary Safety Latch and Lock mechanism is robust, inexpensive, and compact. Applications include safety switches for power distribution panels, industrial control panels, household HVAC, and other service panels in energy applications.

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Augmented Reality in Manufacturing

Jake Stevens, Paul Ryznar, Bill Coe, Will Sommerville, Eve Ryznar, and John Morelli, OPS Solutions, Novi, MI

The Light Guide augmented reality system aids workers by projecting visual display features (VDFs) onto a work surface for operator guidance. It consists of proprietary software, a touchscreen human-machine interface, a PC, and a specialized digital light processing projector.

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“The 3rdArm” — A Wearable Robotic Limb for Augmenting Human Abilities

Roozbeh Khodambashi and Gil Weinberg, Georgia Tech, Atlanta, GA

The 3rdArm general-purpose assistive platform can be used to restore lost function or add new functionality to able-bodied people, amputees, and patients diagnosed with conditions such as brain stroke, MS, or Parkinson’s disease. The technology was initially used to build a wearable robotic limb that allows drummers to play with three arms.

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ARGEE Technology Turns I/O Devices into Field Logic Controllers (FLCs) for Flexible, Cost-Effective Control

Paul Gilbertson, Turck Inc., Plymouth, MN

With ARGEE, manufacturers can add logic to compatible I/O devices to create field logic controllers without a PLC, driving down the cost per I/O point and increasing flexibility in control. Because the I/O devices carry advanced ingress ratings, logic can move outside the control panel and onto machines.

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Gearing the Future — Reluctance Magnetic Gear

Alexandru Sorea, Allan Ivo Søegaard, Flemming Buus Bendixen, Henrick Rasmussen, and Peter Kjeldsteen, Sintex A/S, Hobro, Nordjylland, Denmark

Sintex magnetic gears achieve non-contact, magnetic transmission of torque from one drive to another. The design uses one magnet with a magnetization parallel to the shaft axles, whereas other magnetic gears require many magnets that are difficult to assemble and maintain.

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NASA Tech Briefs Magazine

This article first appeared in the November, 2016 issue of NASA Tech Briefs Magazine.

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