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robot_design:gear_ratios

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robot_design:gear_ratios [2017/06/04 00:10]
biglesliep Initial page content added
robot_design:gear_ratios [2017/06/04 03:36] (current)
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 ==== Use Gears to Get What You Want ==== ==== Use Gears to Get What You Want ====
 So a team has set its priorities are for its given motor use (strength, speed, or [usually] a combination of the two). How to achieve that desired outcome from a VEX motor? With gears! Putting gears in between the motor and the wheel (or turning part) will make the wheel go faster or slower than the motor itself. Looking again at the diagram above, one can also think about this the other way around: the gears will make your wheel/​turning part stronger or weaker than the motor by itself. So a team has set its priorities are for its given motor use (strength, speed, or [usually] a combination of the two). How to achieve that desired outcome from a VEX motor? With gears! Putting gears in between the motor and the wheel (or turning part) will make the wheel go faster or slower than the motor itself. Looking again at the diagram above, one can also think about this the other way around: the gears will make your wheel/​turning part stronger or weaker than the motor by itself.
-===== An Aside: VEX Gear Types ===== 
-VEX gears come in 2 types: standard/​normal strength and high-strength. As shown in the diagram below, high-strength gears have number of features that make them an improvement over the "​standard"​ (thinner) gears. 
-{{ :​robot_design:​gears-normal-vs-high.jpg?​nolink&​600 |Normal vs. High-Strength gears}} 
-  * High-strength gears are about **twice as thick** as standard gears, meaning they are unlikely to crack, and the teeth are less likely to break off. (Everything does have its limits, however; high-strength gears do not come with magic included.) 
-  * The center of the high-strength gear, out of the box, is just a big square hole, and the user chooses which of 2 inserts to put in the middle (or no insert, in the case of high-strength shafts): 
-    * one insert (not shown) makes the center a **round hole** in which a shaft can spin freely; this is useful for idler gears whose shafts are not driving a mechanism, but rather just there to hold a gear; 
-    * the other, shown in the image above, is a **metal insert** that has a square hole that a standard shaft then fits through. These metal inserts are really snug; sometimes they need to be wedged in with a screwdriver,​ pliers, etc., but once they'​re in, they'​re not going anywhere, and they'​re not going to strip. One insert goes on each face of the gear. 
-  * The smallest (12-tooth) gear is **solid metal**, and is not going to crack, even under duress. 
  
-For a **competition robot**, there is no reason to go with the less-reliable standard VEX gears; **high-strength gears are recommended** for their reliability and durability. 
 ===== Gear Ratios ===== ===== Gear Ratios =====
 The phrase "gear ratio" refers to the difference (up or down) in speed between the motor and the end point in a chain of gears (a wheel or other turning part); alternately,​ it can describe the difference in strength (torque) between the motor and the turning part. The phrase "gear ratio" refers to the difference (up or down) in speed between the motor and the end point in a chain of gears (a wheel or other turning part); alternately,​ it can describe the difference in strength (torque) between the motor and the turning part.
robot_design/gear_ratios.txt · Last modified: 2017/06/04 03:36 (external edit)