Automated test hammer

An automated test hammer apparatus, comprising:

• an impact tip;
• a bottom plate;
• an enclosure;
• a top plate;
• an electronics cover;
• magnetic clamps attached to the bottom plate such that they hold the bottom plate in position relative to a structure under test;
• a group of magnets comprising:
• an outer radial magnet ring polarized outward from the center,
• an inner radial magnet ring polarized outward from the center,
• an outer axial magnet ring polarized downward,
• an inner axial magnet ring polarized upward;
• a back-iron that supports the outer radial magnet ring, the inner radial magnet ring, the outer axial magnet ring, and the inner axial magnet ring, the back-iron completing the magnetic circuit between them;
• a load cell connected to the impact tip and connected to the back-iron such that it transmits force from the back-iron to the impact tip;
• shafts supported by the bottom plate and top plate;
• linear bearings that slidably mount the back-iron to the shafts;
• springs between the back-iron and the top plate;
• a bobbin;
• a coil wound around the bobbin residing in the annular space between inner rings and outer rings of the group of magnets;
• and
• wherein current through the coil interacts with the magnetic field of the group of magnets creating an axial force by a Lorentz effect accelerating downward the back-iron, the outer radial magnet ring, the inner radial magnet ring, the outer axial magnet ring, the inner axial magnet ring, the load cell, and the impact tip.