Exoskeleton ; Walking Assistance ; Paraplegic Patients ; Centre of Pressure (CoP)
Abstract
The design of an assistive lower limbexoskeleton robot for paraplegic patients that canmeasurethecentreofpressureispresented.Incontrastwithmostbipedwalkingrobots,thecentreofpressure(CoP) or zero moment point (ZMP) has not beenactivelyusedintheoperationofexoskeletonrobots.Inorderto measure CoP in our exoskeletonrobot,twokinds of force sensor units are installed in theexoskeleton:lowprofileforcesensorsinfootmodulesto measure the human weight transferred to thegroundandaloadcellattheshankframetomeasurethesupportingforce.TheCoPoftheexoskeletonrobot
is calculated from the above force sensors, aninclinometeratthewaist,andthepositionsof14DOFexoskeleton joints with an algorithm to change thefixedpivotusingafootcontactsensor.Experimentsonan able‐bodied person wearing the designedexoskeletonandwalkingonthegroundareperformedto validate the designed hardware system. Throughthe experiments, the trajectory of the CoP of heexoskeletonwithawearerarecalculatedbasedontheproposedalgorithmanditiscomparedwiththevaluemeasured by a commercial pressure measurementsystem.