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Most new aircraft programs encounter the challenge of balancing the time required for design optimization with product delivery constraints. The high cost and long lead times of traditional tooling makes it difficult for aircraft manufactures to efficiently meet ever-changing market demands. The large size, low relative stiffness and high positional tolerances required for aircraft components drive the requirement for rigid fixed tooling to maintain the precision part relationships over time. Use of today’s advance 3-Dimensional CAD systems coupled with the high accuracy of CNC machines enables the success of the determinate assembly approach for aircraft tooling. This approach provides the aircraft manufacturer significant lead-time reductions while at the same time it supports enhanced system flexibility. Determinate assembly for aircraft tooling has been proven to be high successful for tooling manufacture on large-scale system such as the A380 and A340–600 wing assembly projects.

British Aerospace, Airbus Ltd., Chester, UK manufactures the main wing box assembly for all current Airbus programs. Titanium interference fasteners are used in large numbers throughout these aircraft structures. On the lower wing skin of the A320 alone there are approximately 11,000 of this fastener type. Currently, the majority of these fasteners are manually installed using pneumatic or hydraulic tooling. British Aerospace engineers recognized the significant potential which automation offers to reduce these current labor intensive installation methods. Electroimpact proposed extending Low Voltage Electromagnetic Riveter (LVER) technology to the automatic installation of these interference fasteners as well as rivets. Close liaison between Airbus and Electroimpact engineers resulted in the development of an automated LVER based lockbolt installation system, which is currently undergoing evaluation.

The Handheld Low Voltage Electromagnetic Riveter(HHER) has been under development for the past three years. The HHER is an impulse device deriving its power from the discharge of a bank of capacitors through a pancake coil. This gives the HHER the advantage of an accurate and repeatable output force, which results in exceptional consistency in rivet upset dimensions. The rivet/hole interferences obtainable with the HHER have been shown in many cases to be superior to traditional rivet driving techniques, resulting in riveted joints that exhibit excellent fatigue life.(5) Typically, two opposing guns are used on either side of the rivet. These are synchronized through a control cable of arbitrary length. This feature allows accurate installation of slug rivets by hand, a function that in many cases is not possible with existing handheld tools.