Intelligent fasteners with embedded microprocessors remotely controlled by wireless tools or a data network can advance the speed, flexibility, flow, and cost savings that modern production systems require. By integrating assembly logic into the way parts are joined, this technology platform provides designers and manufacturing engineers with a new way to view conventional tools, robots, and assembly processes.

The four elements that make up the Intelligent Fastening Architecture.

Intelligent fasteners have embedded microchips that process commands from a PDA, a PC, or custom-built devices that manage, control, and track assembly and disassembly processes. When the fastener chip receives an electronic signal from the remote tool, it actuates the fastening mechanism, or interrogates the fastener to gauge its status. The remote tool also can communicate with a master database to log or access fastener information.

Conventionally manufactured products use multiple subassemblies with arrays of fasteners that conform to sequencing requirements of production, maintenance, and service processes. With intelligent fasteners, sequencing processes are redefined. Instead of physical or mechanical contact, fasteners lock, unlock, and connect mechanically in response to remote commands transmitted electronically.

Intelligent fastening architecture consists of four elements (see figure):

  • The master control database serves as a central repository and archive for fastener identification, assembly, and service application programs, status and event log, and inventory and logistics components.
  • The remote tool instructs, manages, diagnoses, and documents a network of fasteners as parts are assembled or disassembled. It performs these actions through proprietary software.
  • The communications concentrator provides the operating environment to support onboard networking and communications links to the intelligent tool.
  • The intelligent fastener combines a microprocessor, an energy switch, and sensors to monitor fastener status. The microprocessor can capture a full maintenance history, including dates, times, places, and the operator or technician performing each process. Intelligent fasteners are encrypted with secure addresses and software that respond only to remote instructions entered by authorized users.

Initial applications for intelligent fastening could include shape memory alloys electronically activated by the remote tool. For example, printed circuit boards often are damaged during production by a misaligned tool or over-tightened screws. Intelligent fasteners with smart materials that change shape or state when energized by electric current or heat can be integrated into the PCB. This would allow the board to be fastened to a casing without stopping at a workstation and interrupting production flow.

Intelligent fastening equips designers, engineers, and programmers with the ability to integrate the mechanics of fastening processes into the product. It provides them with the tools to simplify product designs, enhance aesthetics, and advance assembly technology.

This article was written by Seshu Seshasai, executive vice president of technology for Textron Fastening Systems. For further information, contact Textron at 248-813-6330 or visit 

NASA Tech Briefs Magazine

This article first appeared in the February, 2004 issue of NASA Tech Briefs Magazine.

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