A tensile machine with a novel optical load cell for soft biological tissues application

Area of Science:

• Biomaterials Engineering
• Mechanical Engineering
• Tissue Mechanics

Background:

• Uniaxial tensile testing machines are crucial for material mechanical property assessment.
• Existing devices are often costly, limiting access for smaller research facilities.
• There is a need for affordable, high-precision testing equipment for soft biological tissues.

Purpose of the Study:

• To design and fabricate a novel, low-cost uniaxial tensile testing machine.
• To enable accurate measurement of mechanical properties in soft biological tissues.
• To provide a cost-effective solution for small research centers.

Main Methods:

• A new low-cost beam-based load cell was designed, with stiffness determined theoretically and experimentally (100 N/mm).
• Optical deflection measurement of the load cell was achieved using a digital microscope with 1 µm accuracy.
• An in-house image processing program analyzed the force-time behavior of tissue specimens.

Main Results:

• The fabricated uniaxial tensile testing machine accurately measured soft tissue mechanical properties.
• Measurements of amnion tissue demonstrated strong agreement with previously published data.
• The load cell's stiffness was adjustable, accommodating various tissue strengths.

Conclusions:

• The developed low-cost uniaxial tensile testing machine is effective for soft biological tissue analysis.
• This innovation enhances accessibility to advanced mechanical testing for smaller research institutions.
• The device offers a reliable and affordable method for characterizing tissue biomechanics.