Feet Pressure Sensors

Force Sensing Resistor (FSR)

• Price:  $6
• Pros:   meant to mainly measure contact but can also give rough weight measurements . Cheap, already built,  small footprint
• Cons:  Force readings are not very accurate

Lynxmotion Hexapod Foot Senso

• Price:  $20 for a pair
• Pros:   FSR above installed into a form factor intended specifically for hexapod feet.  Consistent construction provides reliable relationship between load and resistance
• Cons:  more expensive than just FSR

Hand Make Styrofoam Pressure Sensor

• Price: ~$0.25 each
• Pros: A cheap and easy way to make pressure sensor that uses the variable resistance of a piece of Styrofoam to determine pressure, can be made as needed, no shipping cost. (A similar design might be able to be adapted to torsion pressure sensors?)
• Cons: Testing would be needed to determine the exact correlation of pressure to the resistance returned by the piece of Styrofoam

Load Sensor

• Price:  $9.95
• Pros: A load sensor that is similar to the design used in most bathroom scales. Measures up to 50kg (110lbs). Tutorials available to help integrate them with micro-controllers. cheap, small footprint  (We may be able to scrap some from old digital scales?) 
• Cons: Their level of accuracy is not listed

BioTach

• Price: ?
• Pros: contains all the sensory capabilities of a human fingertip/toetip. Impedance-sensing electrodes capable of measuring deformations that arise when normal or shear forces are applied to the surface of the skin. Sensitive to different types of surfaces.
• Cons: expensive.  Unnecessary sensitivity? We really don't need to measure things like surface texture