Background: Disorders associated with excessive swelling of the lower extremities are\ncommon. They can be associated with pain, varicose veins, reduced blood pressure\nwhen standing and may cause syncope or fainting. The common physical remedy to\nthese disorders is the use of compression stockings and pneumatic compression leg\nmassagers, which both attempt to limit blood pooling and capillary filtration in the\nlower limbs. However, compression stockings provide a constant pressure, and their\nefficiency has been challenged according to some recent studies. Air compression leg\nmassagers on the other hand, restricts patient mobility. In this work we therefore\npresent an innovative active compression bandage based on the use of a smart\nmaterials technology that could produce intermittent active pressure to mitigate the\nsymptoms of lower extremity disorders.\nMethods: An active compression bandage (ACB), actuated by shape memory alloy\n(SMA) wires, was designed and prototyped. The ACB was wrapped around a calf model\nto apply an initial pressure comparable to the one exerted by commercial compression\nstockings. The ACB was controlled to apply different values of compression. A data\nacquisition board and a LabVIEW program were used to acquire both the pressure data\nexerted by the ACB and the electrical current required to actuate the SMA wires. An\nanalytical model of the ACB based on a SMA constitutive model was developed. An\noptimizer was implemented to identify optimal parameters of the model to best\nestimate the performance of the ACB.\nResults: The maximum increase in pressure due to the SMA wires activation was\n40.8% higher than the initially applied pressure to the calf model. The analytical model\nof the ACB estimated the behaviour of the ACB with less than 0.32 mmHg difference\nwith the experimental results.\nConclusions: The prototyped ACB was able to apply an initial compression\ncomparable to the one applied by commercial compression stockings. Activation of\nthe ACB resulted in an increase of compression up to 9.06 mmHg. Comparison\nbetween analytical and experimental results showed the analytical model was suitable\nto predict the behaviour of the ACB
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