Robust <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.50008pt;width:73.462502px;" id="M1" height="21.450001" version="1.1" viewBox="0 0 73.462502 21.450001" width="73.462502">
	
		
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			<g transform="matrix(.022,-0,0,-.022,27.875,15.825)"><path id="x2F" d="M368 703l-264 -866h-60l265 866h59z"></path></g><g transform="matrix(.022,-0,0,-.022,37.11,15.825)"><use xlink:href="#x1D43B"></use></g>

			<g transform="matrix(.016,-0,0,-.016,56.775,21.2)"><path id="x221E" d="M983 225q0 -112 -67 -174.5t-150 -62.5q-91 0 -154.5 43.5t-113.5 129.5q-49 -85 -104 -129t-138 -44q-98 0 -158.5 66t-60.5 154q0 59 21 106.5t54.5 75.5t70.5 43t73 15q90 0 152.5 -43.5t112.5 -128.5q48 84 104.5 128t140.5 44q93 0 155 -65t62 -158zM478 196
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</svg> Control for the Electrohydraulic Steering System of a Four-Wheel Vehicle

<table>The diagram of the 4WS vehicle.</table>

Mathematical Problems in Engineering

fig3

Figure 3

Figure 3: Robust <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.50008pt;width:73.462502px;" id="M1" height="21.450001" version="1.1" viewBox="0 0 73.462502 21.450001" width="73.462502">
	
		
			<g transform="matrix(.022,-0,0,-.022,.062,15.825)"><path id="x1D43B" d="M865 650q-1 -4 -4 -14t-4 -14q-62 -5 -77 -19.5t-29 -82.5l-74 -394q-12 -61 -0.5 -77t75.5 -21l-6 -28h-273l8 28q64 5 82 21t29 76l36 198h-380l-37 -197q-11 -64 0.5 -78.5t79.5 -19.5l-6 -28h-268l6 28q60 6 75.5 21.5t26.5 76.5l75 394q13 66 2 81.5t-77 20.5l8 28
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			<g transform="matrix(.016,-0,0,-.016,19.725,21.2)"><path id="x32" d="M412 140l28 -9q0 -2 -35 -131h-373v23q112 112 161 170q59 70 92 127t33 115q0 63 -31 98t-86 35q-75 0 -137 -93l-22 20l57 81q55 59 135 59q69 0 118.5 -46.5t49.5 -122.5q0 -62 -29.5 -114t-102.5 -130l-141 -149h186q42 0 58.5 10.5t38.5 56.5z"></path></g>

			<g transform="matrix(.022,-0,0,-.022,27.875,15.825)"><path id="x2F" d="M368 703l-264 -866h-60l265 866h59z"></path></g><g transform="matrix(.022,-0,0,-.022,37.11,15.825)"><use xlink:href="#x1D43B"></use></g>

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</svg> Control for the Electrohydraulic Steering System of a Four-Wheel Vehicle 

Mathematical Problems in Engineering

Robust Control for the Electrohydraulic Steering System of a Four-Wheel Vehicle

Figure 3