Output Feedback Nonlinear <svg style="vertical-align:-4.50008pt;width:34.849998px;" id="M1" height="20.362499" version="1.1" viewBox="0 0 34.849998 20.362499" width="34.849998"  xmlns="http://www.w3.org/2000/svg">
	<g transform="matrix(1.25,0,0,-1.25,0,20.3625)">
		<g transform="translate(72,-55.71)">
			<text transform="matrix(1,0,0,-1,-71.95,60.24)">
				<tspan style="font-size: 17.93px; " x="0" y="0">𝐻</tspan>
			</text>

			<text transform="matrix(1,0,0,-1,-56.29,55.76)">
				<tspan style="font-size: 12.55px; " x="0" y="0">∞</tspan>
			</text>

		</g>
	</g>
</svg>-Tracking Control of a Nonminimum-Phase 2-DOF Underactuated Mechanical System

<table>Schematic diagram of the acrobot where <svg height="14.475" id="M181" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 11.1875 14.475" width="11.1875" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,14.475)">
<g transform="translate(72,-60.42)">
<text transform="matrix(1,0,0,-1,-71.95,63.6)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑙</tspan>
</text>
<text transform="matrix(1,0,0,-1,-67.97,60.47)">
<tspan style="font-size: 8.75px; " x="0" y="0">1</tspan>
</text>
</g>
</g>
</svg> and <svg height="14.475" id="M182" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 11.1875 14.475" width="11.1875" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,14.475)">
<g transform="translate(72,-60.42)">
<text transform="matrix(1,0,0,-1,-71.95,63.6)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑙</tspan>
</text>
<text transform="matrix(1,0,0,-1,-67.97,60.47)">
<tspan style="font-size: 8.75px; " x="0" y="0">2</tspan>
</text>
</g>
</g>
</svg> denote the length of the nonactuated and actuated links, respectively; and <svg height="10.925" id="M183" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 17.3125 10.925" width="17.3125" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,10.925)">
<g transform="translate(72,-63.26)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑚</tspan>
</text>
<text transform="matrix(1,0,0,-1,-63.07,63.31)">
<tspan style="font-size: 8.75px; " x="0" y="0">1</tspan>
</text>
</g>
</g>
</svg> and <svg height="10.925" id="M184" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 17.3125 10.925" width="17.3125" xmlns="http://www.w3.org/2000/svg">
<g transform="matrix(1.25,0,0,-1.25,0,10.925)">
<g transform="translate(72,-63.26)">
<text transform="matrix(1,0,0,-1,-71.95,66.44)">
<tspan style="font-size: 12.50px; " x="0" y="0">𝑚</tspan>
</text>
<text transform="matrix(1,0,0,-1,-63.07,63.31)">
<tspan style="font-size: 8.75px; " x="0" y="0">2</tspan>
</text>
</g>
</g>
</svg> are the masses of each link.</table>

Journal of Robotics

fig3

Figure 3

Figure 3: Output Feedback Nonlinear <svg style="vertical-align:-4.50008pt;width:34.849998px;" id="M1" height="20.362499" version="1.1" viewBox="0 0 34.849998 20.362499" width="34.849998"  xmlns="http://www.w3.org/2000/svg">
	<g transform="matrix(1.25,0,0,-1.25,0,20.3625)">
		<g transform="translate(72,-55.71)">
			<text transform="matrix(1,0,0,-1,-71.95,60.24)">
				<tspan style="font-size: 17.93px; " x="0" y="0">𝐻</tspan>
			</text>

			<text transform="matrix(1,0,0,-1,-56.29,55.76)">
				<tspan style="font-size: 12.55px; " x="0" y="0">∞</tspan>
			</text>

		</g>
	</g>
</svg>-Tracking Control of a Nonminimum-Phase 2-DOF Underactuated Mechanical System 

Figure 3 | Output Feedback Nonlinear 
	
		
			
				𝐻
			

			
				∞
			

		
	
-Tracking Control of a Nonminimum-Phase 2-DOF Underactuated Mechanical System 

Journal of Robotics

Output Feedback Nonlinear 𝐻 ∞ -Tracking Control of a Nonminimum-Phase 2-DOF Underactuated Mechanical System

Figure 3

Output Feedback Nonlinear -Tracking Control of a Nonminimum-Phase 2-DOF Underactuated Mechanical System