{"id":6328,"date":"2019-09-03T13:34:56","date_gmt":"2019-09-03T17:34:56","guid":{"rendered":"https:\/\/dronebotworkshop.com\/?p=6328"},"modified":"2023-04-12T11:18:02","modified_gmt":"2023-04-12T15:18:02","slug":"stepper-motor-hall-effect","status":"publish","type":"post","link":"https:\/\/dronebotworkshop.com\/stepper-motor-hall-effect\/","title":{"rendered":"Stepper Motor with Hall Effect Limit & Homing Switches"},"content":{"rendered":"\n

\"Download \"Parts<\/a> \"View<\/a> \"Download<\/p>\n

Introduction<\/span><\/h2>\n

Today we will look at implementing both limit switches and homing sensors for a stepper motor.<\/span><\/p>\n

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We have used stepper motors in many of our projects and experiments, and for good reason. Stepper motors allow precise control of their shaft position, using microstepping you can control this to a fraction of a degree.\u00a0 This is why stepper motors find use in application like printers and DVD drives, they are a great choice anytime a powerful yet precise motor is required.<\/span><\/p>\n

But, unlike servo motors, stepper motors do not normally have an internal feedback mechanism to determine the current shaft position. So when your stepper-based project is first powered up it really has no idea what position the motor shaft is currently sitting at.\u00a0<\/span><\/p>\n

\"Stepper<\/p>\n

In some cases, you really don\u2019t care what the current shaft position is, but you do want to know when the stepper (or the mechanical devices being driven by the stepper) has reached a certain point in its travel so you can stop or reverse the motor.<\/span><\/p>\n

Fortunately, there are a couple of ways to resolve these issues.\u00a0 We\u2019ll take a look at a couple of methods today.<\/span><\/p>\n

Limit Switches and Homing Sensors<\/span><\/h2>\n

Limit switches and homing sensors are ways of determining the position of either the stepper motor shaft itself or of the mechanism that the shaft is powering.\u00a0\u00a0<\/span><\/p>\n

Both schemes use switches of some sort that are activated when the shaft or mechanism reaches a certain position.<\/span><\/p>\n

Limit Switches<\/i><\/b> are generally used in pairs and are placed at the mechanisms the end of travel. Once the switch is activated the motor will respond, how it responds is entirely up to you, but in most cases, it will either stop or reverse.<\/span><\/p>\n

A <\/span>Homing Sensor<\/i><\/b> or switch is placed in a predetermined position to provide a reference point. Once it is activated the motor \u201cknows\u201d where it is. From there you can use the precision of the stepper motor to accurately move into any position you wish.<\/span><\/p>\n

A common use of the homing sensor that you are probably familiar with is in a printer.\u00a0 Many printers go through a sequence of operations when they are powered up, and one of them is to move the print carriage to the homing position to get a reference point.<\/span><\/p>\n

Types of Switches<\/span><\/h3>\n

You can use many kinds of switches to build homing sensors and limit switches.\u00a0<\/span><\/p>\n