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3,993 bytes added, 17:39, 31 March 2016

Axis Resolution - counts/inch (or counts/mm)

<div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;">It is usually best to first determine max possible velocity using a relatively low acceleration. Maximum power is usually required at the point of the trajectory where velocity is high and still accelerating. Supply Voltage limitations tend to limit velocity. Current limitations tend to limit acceleration.<br /><br /></div>

<div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;"><div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;">[[File:MaxVelAccelPower.png|none|link=|485x361px]]<br />The Step Response Screen always performs 3rd order motion but 2nd order motion can be simulated by temporarily setting the Jerk to a huge value (1000X the acceleration value). In general reducing the Jerk value will result in longer times to perform motions, but often the improved smoothness will permit higher maximum accelerations and velocities to be used resulting in overall shorter motion times. An analogy might be how you might stop more quickly in a car, without skidding or spilling your coffee, by applying the brakes harder in a more gradual manner rather than slamming on the brakes.<br /><br /><span class="yiv2818182665class">Make</span> sure when testing the size of move is long enough for full acceleration and velocity are achieved. As a common mistake is to have Acceleration or Velocity Settings set to too high for your system but when testing a short move there is no indication of a problem. The plot mode of Velocity Output vs Time can be helpful to verify full Velocity is being achieved.<span id=".C2.A0" class="mw-headline"> <br /></span></div><div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;"> </div>

===<span class="mw-headline">Axis Resolution - counts/inch (or counts/mm)</span>===

<div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;"><span class="mw-headline">Its important to understand the resolution of your Axis which is the number of fundamental raw motor/driver encoder counts or motor steps per standard unit of distance (inch or mm). Although tuning in KMotion.exe Ste Response Screen and motions within KFLOP typically use units of raw counts or steps it is important to know how these translate to real-world distances, speeds, etc... Later, applications such as KMotionCNC or Mach3 will need this information to scale motions properly.<br /></span></div>

<div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;"><span class="mw-headline">There are usually a number of factors that combine together to determine the Axis Resolution. These might include:</span></div>

* <span class="mw-headline">counts or steps per motor revolution</span>

* <span class="mw-headline">any gearing or belts and pulleys involved between motor and drive mechanisms</span>

* <span class="mw-headline">lead screw pitch, rack and pinion tooth pitch, drive belt radius, etc.</span>

<span class="mw-headline">For example consider a Stepper Drive with:</span>

<span class="mw-headline">3200 steps per motor rev</span>

<span class="mw-headline">2:1 gear reduction from motor to lead screw</span>

<span class="mw-headline">0.2 inch lead screw pitch</span>

<span class="mw-headline">Axis Resolution = 3200 step/motor rev x (2 motor rev/ screw rev) / (0.2 inch / screw rev) = 32000 steps/inch</span>

<span class="mw-headline">To determine whether your assumptions and calculations are correct perform a test. Command as large of a move as convenient and measure the actual distance moved with a ruler. For example in the axis described above you might command a move of 320000 steps. This should result in a motion of:</span>

<span class="mw-headline">320000 steps / (32000 steps/inch) = 10 inches.</span>

<span class="mw-headline">For KMotionCNC set the Axis Resolution in the [http://dynomotion.com/Help/KMotionCNC/ToolSetupScreenTP.htm#Axis_Motion_Parameters Tool Setup | Trajectory Planner Screen | Axis Parameters | cnts/inch]. Note units must be in units of inches. If your resolution is in mm units multiply by 25.4.</span>

<span class="mw-headline">For Mach3 enter the Axis Resolution in the Configuration | Motor Tuning Screen. Make sure the setup units (not GCode units) match the mode of your values.</span>

===Noisy GCode - Trajectory Planner Smoothing===

<div class="yiv2818182665class" style="color: #000000; font-size: 13.3333px; font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; background-color: transparent; font-style: normal;">An analysis of Quantization Noise in GCode and Trajectory Planner Settings to generate smooth motion.<br />[[File:GCode_Noisy_Path.png|none|link=|432x432px]]</div>

==Problems and Resolutions==

====General====

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