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<title>Open-loop controller</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Open-loop controller</span></span>

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</style><div role="note" class="hatnote navigation-not-searchable">"Open loop" redirects here. For other uses, see <a href="Open_loop_(disambiguation)" class="mw-disambig" title="Open loop (disambiguation)">Open loop (disambiguation)</a>.</div>

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<p>In <a href="Control_theory" title="Control theory">control theory</a>, an <b>open-loop controller</b>, also called a <b>non-feedback controller</b>, is a <a href="Control_loop" title="Control loop">control loop</a> part of a <a href="Control_system" title="Control system">control system</a> in which the control action ("input" to the system<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>) is independent of the "process output", which is the <a href="Process_variable" title="Process variable">process variable</a> that is being controlled.<sup id="cite_ref-auto_2-0" class="reference"><a href="#cite_note-auto-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> It does not use <a href="Feedback" title="Feedback">feedback</a> to determine if its output has achieved the desired goal of the input command or process <a href="Setpoint_(control_system)" title="Setpoint (control system)">setpoint</a>.

</p><p>There are many open-<a href="Control_loop" title="Control loop">loop</a> controls, such as on/off switching of valves, machinery, lights, motors or heaters, where the control result is known to be approximately sufficient under normal conditions without the need for feedback. The advantage of using open-loop control in these cases is the reduction in component count and complexity. However, an open-loop system cannot correct any errors that it makes or correct for outside disturbances unlike a <a href="Closed-loop_control_system" class="mw-redirect" title="Closed-loop control system">closed-loop control system</a>.

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<div class="mw-heading mw-heading2"><h2 id="Open-loop_and_closed-loop">Open-loop and closed-loop</h2></div>

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</style><div role="note" class="hatnote navigation-not-searchable dablink excerpt-hat selfref">This section is an excerpt from <a href="Control_loop#Open-loop_and_closed-loop" title="Control loop">Control loop § Open-loop and closed-loop</a>.<span class="mw-editsection-like "><span class="mw-editsection-bracket">[</span><a class="external text external" href="https://en.wikipedia.org/w/index.php?title=Control_loop&action=edit#Open-loop_and_closed-loop">edit</a><span class="mw-editsection-bracket">]</span></span></div><div class="excerpt">

<p>Fundamentally, there are two types of control loop: <i><a href="Open-loop_control" class="mw-redirect" title="Open-loop control">open-loop control</a></i> (feedforward), and <i><a href="Closed-loop_control" class="mw-redirect" title="Closed-loop control">closed-loop control</a></i> (feedback).

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<ul><li>In open-loop control, the control action from the controller is independent of the "process output" (or "controlled process variable"). A good example of this is a central heating boiler controlled only by a timer, so that heat is applied for a constant time, regardless of the temperature of the building. The control action is the switching on/off of the boiler, but the controlled variable should be the building temperature, but is not because this is open-loop control of the boiler, which does not give closed-loop control of the temperature.</li>

<li>In closed loop control, the control action from the controller is dependent on the process output. In the case of the boiler analogy, this would include a thermostat to monitor the building temperature, and thereby feed back a signal to ensure the controller maintains the building at the temperature set on the thermostat. A closed loop controller therefore has a feedback loop which ensures the controller exerts a control action to give a process output the same as the "reference input" or "set point". For this reason, closed loop controllers are also called feedback controllers.<sup id="cite_ref-Control_loop_auto_3-0" class="reference"><a href="#cite_note-Control_loop_auto-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></li></ul>

<p>The definition of a closed loop control system according to the <a href="British_Standards_Institution" class="mw-redirect" title="British Standards Institution">British Standards Institution</a> is "a control system possessing monitoring feedback, the deviation signal formed as a result of this feedback being used to control the action of a final control element in such a way as to tend to reduce the deviation to zero."<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>

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Likewise; "A <i>Feedback Control System</i> is a system which tends to maintain a prescribed relationship of one system variable to another by comparing functions of these variables and using the difference as a means of control."<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></div></div>

<div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2></div>

<p>An open-loop controller is often used in simple processes because of its simplicity and low cost, especially in systems where feedback is not critical. A typical example would be an older model domestic <a href="Clothes_dryer" title="Clothes dryer">clothes dryer</a>, for which the length of time is entirely dependent on the judgement of the human operator, with no automatic feedback of the dryness of the clothes.

</p><p>For example, an <a href="Irrigation_sprinkler" title="Irrigation sprinkler">irrigation sprinkler</a> system, programmed to turn on at set times could be an example of an open-loop system if it does not measure <a href="Soil" title="Soil">soil</a> <a href="Moisture" title="Moisture">moisture</a> as a form of feedback. Even if rain is pouring down on the lawn, the sprinkler system would activate on schedule, wasting water.

</p><p>Another example is a <a href="Stepper_motor" title="Stepper motor">stepper motor</a> used for control of position. Sending it a stream of electrical pulses causes it to rotate by exactly that many steps, hence the name. If the motor was always assumed to perform each movement correctly, without positional feedback, it would be open-loop control. However, if there is a position encoder, or sensors to indicate the start or finish positions, then that is closed-loop control, such as in many <a href="Inkjet_printer" class="mw-redirect" title="Inkjet printer">inkjet printers</a>. The drawback of open-loop control of steppers is that if the machine load is too high, or the motor attempts to move too quickly, then steps may be skipped. The controller has no means of detecting this and so the machine continues to run slightly out of adjustment until reset. For this reason, more complex robots and machine tools instead use <a href="Servomotor" title="Servomotor">servomotors</a> rather than stepper motors, which incorporate <a href="Rotary_encoder" title="Rotary encoder">encoders</a> and <a href="Closed-loop_controller" title="Closed-loop controller">closed-loop controllers</a>.

</p><p>However, open-loop control is very useful and economic for well-defined systems where the relationship between input and the resultant state can be reliably modeled by a mathematical formula. For example, determining the <a href="Voltage" title="Voltage">voltage</a> to be fed to an <a href="Electric_motor" title="Electric motor">electric motor</a> that drives a constant load, in order to achieve a desired <a href="Speed" title="Speed">speed</a> would be a good application. But if the load were not predictable and became excessive, the motor's speed might vary as a function of the load not just the voltage, and an open-loop controller would be insufficient to ensure repeatable control of the velocity.

</p><p>An example of this is a conveyor system that is required to travel at a constant speed. For a constant voltage, the conveyor will move at a different speed depending on the load on the motor (represented here by the weight of objects on the conveyor). In order for the conveyor to run at a constant speed, the voltage of the motor must be adjusted depending on the load. In this case, a closed-loop control system would be necessary.

</p><p>Thus there are many open-loop controls, such as switching valves, lights, motors or heaters on and off, where the result is known to be approximately sufficient without the need for feedback.

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<div class="mw-heading mw-heading2"><h2 id="Combination_with_feedback_control">Combination with feedback control</h2></div>

<p>A feed back control system, such as a <a href="PID_controller" class="mw-redirect" title="PID controller">PID controller</a>, can be improved by combining the <a href="Feedback" title="Feedback">feedback</a> (or <a href="Closed-loop_control" class="mw-redirect" title="Closed-loop control">closed-loop control</a>) of a PID controller with <a href="Feed_forward_(control)" title="Feed forward (control)">feed-forward</a> (or open-loop) control. Knowledge about the system (such as the desired acceleration and inertia) can be fed forward and combined with the PID output to improve the overall system performance. The feed-forward value alone can often provide the major portion of the controller output. The PID controller primarily has to compensate whatever difference or <i>error</i> remains between the setpoint (SP) and the system response to the open-loop control. Since the feed-forward output is not affected by the process feedback, it can never cause the control system to oscillate, thus improving the system response without affecting stability. Feed forward can be based on the setpoint and on extra measured disturbances. Setpoint weighting is a simple form of feed forward.

</p><p>For example, in most motion control systems, in order to accelerate a mechanical load under control, more force is required from the actuator. If a velocity loop PID controller is being used to control the speed of the load and command the force being applied by the actuator, then it is beneficial to take the desired instantaneous acceleration, scale that value appropriately and add it to the output of the PID velocity loop controller. This means that whenever the load is being accelerated or decelerated, a proportional amount of force is commanded from the actuator regardless of the feedback value. The PID loop in this situation uses the feedback information to change the combined output to reduce the remaining difference between the process setpoint and the feedback value. Working together, the combined open-loop feed-forward controller and closed-loop PID controller can provide a more responsive control system in some situations.

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<ul><li><a href="Cataract_(beam_engine)" title="Cataract (beam engine)">Cataract</a>, the open-loop speed controller of early <a href="Beam_engine" title="Beam engine">beam engines</a></li>

<li><a href="Control_theory" title="Control theory">Control theory</a></li>

<li><a href="Feed_forward_(control)" title="Feed forward (control)">Feed-forward</a></li>

<li><a href="PID_controller" class="mw-redirect" title="PID controller">PID controller</a></li>

<li><a href="Process_control" class="mw-redirect" title="Process control">Process control</a></li>

<li><a href="Open-loop_transfer_function" class="mw-redirect" title="Open-loop transfer function">Open-loop transfer function</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFEscudierAtkins2019" class="citation journal cs1">Escudier, Marcel; Atkins, Tony (2019). <span class="id-lock-subscription" title="Paid subscription required"><a rel="nofollow" class="external text" href="https://dx.doi.org/10.1093/acref/9780198832102.001.0001">"A Dictionary of Mechanical Engineering"</a></span>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1093%2Facref%2F9780198832102.001.0001">10.1093/acref/9780198832102.001.0001</a>. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-19-883210-2</bdi>.</cite> <span class="cs1-visible-error citation-comment"><code class="cs1-code">{{cite journal}}</code>: </span><span class="cs1-visible-error citation-comment">Cite journal requires <code class="cs1-code">|journal=</code> (help)</span></span>

</li>

<li id="cite_note-auto-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-auto_2-0">^</a></b></span> <span class="reference-text">"Feedback and control systems" - JJ Di Steffano, AR Stubberud, IJ Williams. Schaums outline series, McGraw-Hill 1967</span>

</li>

<li id="cite_note-Control_loop_auto-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-Control_loop_auto_3-0">^</a></b></span> <span class="reference-text">"Feedback and control systems" - JJ Di Steffano, AR Stubberud, IJ Williams. Schaums outline series, McGraw-Hill 1967</span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite id="CITEREFMayr1970" class="citation book cs1"><a href="Otto_Mayr" title="Otto Mayr">Mayr, Otto</a> (1970). <i>The Origins of Feedback Control</i>. Clinton, MA US: The Colonial Press, Inc.</cite></span>

</li>

<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><cite id="CITEREFMayr1969" class="citation book cs1"><a href="Otto_Mayr" title="Otto Mayr">Mayr, Otto</a> (1969). <i>The Origins of Feedback Control</i>. Clinton, MA US: The Colonial Press, Inc.</cite></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>

<ul><li>Kuo, Benjamin C. (1991). <i>Automatic Control Systems</i> (6th ed.). New Jersey: Prentice Hall. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-13-051046-7</bdi>.</li>

<li>Ziny Flikop (2004). "Bounded-Input Bounded-Predefined-Control Bounded-Output" (<a rel="nofollow" class="external free" href="http://arXiv.org/pdf/cs/0411015">http://arXiv.org/pdf/cs/0411015</a>)</li>

<li>Basso, Christophe (2012). "Designing Control Loops for Linear and Switching Power Supplies: A Tutorial Guide". Artech House, <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1608075577</bdi></li></ul>

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</style><div id="Electric_machines473" style="font-size:114%;margin:0 4em"><a href="Electric_machine" title="Electric machine">Electric machines</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div>

<ul><li>AC - <a href="Alternating_current" title="Alternating current">Alternating current</a></li>

<li>DC - <a href="Direct_current" title="Direct current">Direct current</a></li>

<li>PM - <a href="Magnet" title="Magnet">Permanent magnet</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Components</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Rotor_(electric)" title="Rotor (electric)">Rotor</a></li>

<li><a href="Stator" title="Stator">Stator</a></li>

<li><a href="Electromagnetic_coil" title="Electromagnetic coil">Winding</a>

<ul><li><a href="Armature_(electrical)" title="Armature (electrical)">Armature</a></li>

<li><a href="Field_coil" title="Field coil">Field coil</a></li>

<li><a href="Damper_winding" title="Damper winding">Damper winding</a></li></ul></li>

<li><a href="Commutator_(electric)" title="Commutator (electric)">Commutator</a></li>

<li><a href="Brush_(electric)" title="Brush (electric)">Brush</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Electric_generator" title="Electric generator">Generators</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="AC_generator" class="mw-redirect" title="AC generator">AC generator</a>

<ul><li><a href="Alternator" title="Alternator">Alternator</a>

<ul><li><a href="Flux_switching_alternator" title="Flux switching alternator">Flux switching alternator</a></li>

<li><a href="Linear_alternator" title="Linear alternator">Linear alternator</a></li>

<li><a href="Permanent_magnet_synchronous_generator" title="Permanent magnet synchronous generator">PM synchronous generator</a></li>

<li><a href="Magneto" title="Magneto">Magneto</a></li></ul></li>

<li><a href="Induction_generator" title="Induction generator">Induction generator</a>

<ul><li><a href="Doubly_fed_induction_generator" class="mw-redirect" title="Doubly fed induction generator">Doubly fed induction generator</a></li></ul></li>

<li><a href="Single-phase_generator" title="Single-phase generator">Single-phase generator</a></li></ul></li>

<li><a href="DC_generator" class="mw-redirect" title="DC generator">DC generator</a>

<ul><li><a href="Dynamo" title="Dynamo">Dynamo</a></li>

<li><a href="Homopolar_generator" title="Homopolar generator">Homopolar generator</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Electric_motor" title="Electric motor">Motors</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="AC_motor" title="AC motor">AC motor</a>

<ul><li><a href="Induction_motor" title="Induction motor">Induction motor</a>

<ul><li><a href="Shaded-pole_motor" title="Shaded-pole motor">Shaded-pole motor</a></li>

<li><a href="Dahlander_pole_changing_motor" title="Dahlander pole changing motor">Dahlander pole changing motor</a></li>

<li><a href="Wound_rotor_motor" title="Wound rotor motor">Wound rotor motor</a></li>

<li><a href="Linear_induction_motor" title="Linear induction motor">Linear induction motor</a></li>

<li><a href="Doubly_fed_electric_machine" title="Doubly fed electric machine">Doubly fed electric machine</a></li></ul></li>

<li><a href="Synchronous_motor" title="Synchronous motor">Synchronous motor</a></li>

<li><a href="Repulsion_motor" title="Repulsion motor">Repulsion motor</a></li></ul></li>

<li><a href="DC_motor" title="DC motor">DC motor</a>

<ul><li><a href="Brushed_DC_electric_motor" title="Brushed DC electric motor">Brushed DC electric motor</a></li>

<li><a href="Brushless_DC_electric_motor" title="Brushless DC electric motor">Brushless DC electric motor</a>

<ul><li><a href="Stepper_motor" title="Stepper motor">Stepper motor</a></li></ul></li>

<li><a href="Homopolar_motor" title="Homopolar motor">Homopolar motor</a>/<a href="Unipolar_motor" title="Unipolar motor">Unipolar motor</a></li></ul></li>

<li><a href="Universal_motor" title="Universal motor">Universal motor</a></li>

<li><a href="Reluctance_motor" title="Reluctance motor">Reluctance motor</a>

<ul><li><a href="Switched_reluctance_motor" title="Switched reluctance motor">Switched reluctance motor</a></li>

<li><a href="Synchronous_reluctance_motor" class="mw-redirect" title="Synchronous reluctance motor">Synchronous reluctance motor</a></li></ul></li>

<li><a href="Axial_flux_motor" title="Axial flux motor">Axial flux motor</a></li>

<li><a href="Radial_flux_motor" title="Radial flux motor">Radial flux motor</a></li>

<li><a href="Permanent_magnet_motor" title="Permanent magnet motor">PM motor</a></li>

<li><a href="Dual-rotor_motor" title="Dual-rotor motor">Dual-rotor motor</a></li>

<li><a href="Linear_motor" title="Linear motor">Linear motor</a></li>

<li><a href="Ball_bearing_motor" title="Ball bearing motor">Ball bearing motor</a></li>

<li><a href="Electrostatic_motor" title="Electrostatic motor">Electrostatic motor</a></li>

<li><a href="Piezoelectric_motor" title="Piezoelectric motor">Piezoelectric motor</a>

<ul><li><a href="Ultrasonic_motor" title="Ultrasonic motor">Ultrasonic motor</a></li></ul></li>

<li><a href="Servomotor" title="Servomotor">Servomotor</a></li>

<li><a href="Traction_motor" title="Traction motor">Traction motor</a></li>

<li><a href="TEFC_motor" title="TEFC motor">TEFC motor</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Motor_controller" title="Motor controller">Motor controllers</a> and<br>other accessories</div></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="AC-to-AC_converter" title="AC-to-AC converter">AC-to-AC converter</a>

<ul><li><a href="Cycloconverter" title="Cycloconverter">Cycloconverter</a></li></ul></li>

<li><a href="Amplidyne" title="Amplidyne">Amplidyne</a></li>

<li><a href="Motor_drive" title="Motor drive">Drives</a>

<ul><li><a href="Variable-frequency_drive" title="Variable-frequency drive">Variable-frequency drive</a>

<ul><li><a href="Direct_torque_control" title="Direct torque control">Direct torque control</a></li>

<li><a href="Vector_control_(motor)" title="Vector control (motor)">Vector control</a></li></ul></li></ul></li>

<li><a href="Metadyne" title="Metadyne">Metadyne</a></li>

<li><a href="Motor_soft_starter" title="Motor soft starter">Motor soft starter</a></li>

<li><a href="Ward_Leonard_control" title="Ward Leonard control">Ward Leonard control</a></li>

<li><a href="Braking_chopper" title="Braking chopper">Braking chopper</a></li>

<li><a href="DC_injection_braking" title="DC injection braking">DC injection brake module</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">History, education,<br>recreational use</div></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Timeline_of_the_electric_motor" title="Timeline of the electric motor">Timeline of the electric motor</a></li>

<li><a href="Barlow's_wheel" title="Barlow's wheel">Barlow's wheel</a></li>

<li><a href="Lynch_motor" title="Lynch motor">Lynch motor</a></li>

<li><a href="Mendocino_motor" title="Mendocino motor">Mendocino motor</a></li>

<li><a href="Mouse_mill_motor" title="Mouse mill motor">Mouse mill motor</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Experimental, futuristic</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Coilgun" title="Coilgun">Coilgun</a></li>

<li><a href="Railgun" title="Railgun">Railgun</a></li>

<li><a href="Superconducting_electric_machine" title="Superconducting electric machine">Superconducting machine</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related topics</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Blocked_rotor_test" title="Blocked rotor test">Blocked-rotor test</a></li>

<li><a href="Circle_diagram" title="Circle diagram">Circle diagram</a></li>

<li><a href="Coil_winding_technology" title="Coil winding technology">Coil winding technology</a></li>

<li><a href="Electromagnetism" title="Electromagnetism">Electromagnetism</a></li>

<li><a href="Open-circuit_test" title="Open-circuit test">Open-circuit test</a></li>

<li><a href="Power-to-weight_ratio" title="Power-to-weight ratio">Power-to-weight ratio</a></li>

<li><a href="Two-phase_electric_power" title="Two-phase electric power">Two-phase system</a></li>

<li><a href="Inchworm_motor" title="Inchworm motor">Inchworm motor</a></li>

<li><a href="Starter_(engine)" title="Starter (engine)">Starter</a></li>

<li><a href="Voltage_controller" title="Voltage controller">Voltage controller</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">People</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Fran%C3%A7ois_Arago" title="François Arago">Arago</a></li>

<li><a href="Peter_Barlow_(mathematician)" title="Peter Barlow (mathematician)">Barlow</a></li>

<li><a href="Giuseppe_Domenico_Botto" title="Giuseppe Domenico Botto">Botto</a></li>

<li><a href="Thomas_Davenport_(inventor)" title="Thomas Davenport (inventor)">Davenport</a></li>

<li><a href="Robert_Davidson_(inventor)" title="Robert Davidson (inventor)">Davidson</a></li>

<li><a href="Mikhail_Dolivo-Dobrovolsky" title="Mikhail Dolivo-Dobrovolsky">Dolivo-Dobrovolsky</a></li>

<li><a href="Michael_Faraday" title="Michael Faraday">Faraday</a></li>

<li><a href="Galileo_Ferraris" title="Galileo Ferraris">Ferraris</a></li>

<li><a href="Z%C3%A9nobe_Gramme" title="Zénobe Gramme">Gramme</a></li>

<li><a href="Joseph_Henry" title="Joseph Henry">Henry</a></li>

<li><a href="Moritz_von_Jacobi" title="Moritz von Jacobi">Jacobi</a></li>

<li><a href="%C3%81nyos_Jedlik" title="Ányos Jedlik">Jedlik</a></li>

<li><a href="James_Clerk_Maxwell" title="James Clerk Maxwell">Maxwell</a></li>

<li><a href="Hans_Christian_%C3%98rsted" title="Hans Christian Ørsted">Ørsted</a></li>

<li><a href="Antonio_Pacinotti" title="Antonio Pacinotti">Pacinotti</a></li>

<li><a href="Hippolyte_Pixii" title="Hippolyte Pixii">Pixii</a></li>

<li><a href="Joseph_Saxton" title="Joseph Saxton">Saxton</a></li>

<li><a href="Werner_von_Siemens" title="Werner von Siemens">Siemens</a></li>

<li><a href="Frank_J._Sprague" title="Frank J. Sprague">Sprague</a></li>

<li><a href="Charles_Proteus_Steinmetz" title="Charles Proteus Steinmetz">Steinmetz</a></li>

<li><a href="William_Sturgeon" title="William Sturgeon">Sturgeon</a></li>

<li><a href="Nikola_Tesla" title="Nikola Tesla">Tesla</a></li></ul>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-05-25" href="https://en.wikipedia.org/wiki/?title=Open-loop_controller&oldid=1292137098">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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