<div class="htmlview paragraph">An electronically controlled Easy Drive System (EDS), the NAVI-5, is now used in the Isuzu Aska, to permit automatic gear changes with in the basic structure of a manual transmission. This is achieved by synchromeshed transmission gears and a single disk dry clutch operated by hydraulic actuators and controlled by a microcomputer which is based on a unique digital algorithm. However this technical feasibility for use in the field has hitherto been considered difficult. At the same time, excellent engine power and fuel economy equal to that attainable with the conventional manual transmission have been achieved using this system which makes maximum use of the advantage of its manual transmission construction.</div> <div class="htmlview paragraph">This paper describes an actuator for the clutch, which makes complex clutch operation possible and has the following features: <ol class="list nostyle"> <li class="list-item"><span class="li-label">(1)</span> <div class="htmlview paragraph">High speed solenoid valves, which are simply constructed and highly durable.</div></li> <li class="list-item"><span class="li-label">(2)</span> <div class="htmlview paragraph">A closed loop control which feeds back clutch stroke.</div></li> <li class="list-item"><span class="li-label">(3)</span> <div class="htmlview paragraph">A pulse width modulating (PWM) control suitable for a microcomputer.</div></li> </ol></div>