A Comparison between Two Force-Position Controllers with Gravity Compensation Simulated on a Humanoid Arm

<table>End-Effector force value (N) varying the <svg height="15.25" id="M127" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 21.3375 15.25" width="21.3375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> gain in the PI system: (a) <svg height="15.25" id="M128" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 85.4375 15.25" width="85.4375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.017,-0,0,-.017,26,11.112)"><path d="M535 323h-483v50h483v-50zM535 138h-483v50h483v-50z" id="x3D"></path></g><g transform="matrix(.017,-0,0,-.017,40.687,11.112)"><path d="M241 635q53 0 94 -28.5t63.5 -76t33.5 -102.5t11 -116q0 -58 -11 -112.5t-34 -103.5t-63.5 -78.5t-94.5 -29.5t-95 28t-64.5 75t-34.5 102.5t-11 118.5q0 58 11.5 112.5t34.5 103t64.5 78t95.5 29.5zM238 602q-32 0 -55.5 -25t-35.5 -68t-17.5 -91t-5.5 -105
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</svg>; (b) <svg height="15.25" id="M129" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 77.275002 15.25" width="77.275002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>.</table>

Journal of Robotics

fig20

Figure 20

Figure 20: A Comparison between Two Force-Position Controllers with Gravity Compensation Simulated on a Humanoid Arm 