|
Tech Focus: (Micro) step up to motor control
HIGHLIGHTS
A simple algorithm for microstepping a bipolar stepper motor
Linear motor control without the math
Generate stepper-motor speed profiles in real time
Editor's Note
My top featured design article for this issue of Embedded Tech Focus is “A simple algorithm for microstepping a bipolar stepper motor” by TI’s Jose Quinones. After reading it I decided to brush up (excuse the pun ) on brushless stepper electric motors. Talk about hiding in plain sight! Now I find it hard not to see them everywhere.
Microprocessor-controlled stepper motors are one of the most versatile forms of positioning systems, used in industrial control, lasers and optics, automobiles, computer disk drives, flatbed scanners, printers, plotters and slot machines among many apps. And with MEMS, they are used in numerous embedded consumer and mobile designs as well.
Given their ubiquity, it is no surprise that embedded systems designers devote a lot of imagination to coming up with innovative ways to make MCU-controlled steppers and microsteppers do more and do it better, faster, and with lower power. Of the many articles on the topic included here, my Editor’s Top Picks are:
Generate stepper-motor speed profiles in real time
Designing more efficient stepper motor control subsystems
Choosing the right driver/controller for your stepper design
In addition to the design articles, webinars and white papers here, I created a Google list of on-line videos of MCU stepper related lectures, tutorials, and hands-on DIY examples, all organized by date.
If you find this Tech Focus useful, save it in your email list for future reference or follow the instructions above to view the newsletter online and save it to your browser favorites list. Online search engines are great but using them is like reading a reference book with only the index at the end to guide you. An easier way to access the information you need is to use the Embedded newsletters as your Table of Contents for design information on the Embedded.com site and in ESD Magazine .
Design How Tos
A simple algorithm for microstepping a bipolar stepper motor
This article details a simple algorithm utilizing conventional microcontroller blocks to control commercially available H-bridges to properly commutate a bipolar stepper motor through a microstepping profile.
Linear motor control without the math
A new algorithm using only addition and subtraction and no complicated math produces the linear acceleration necessary to run a step motor smoothly.
Designing more efficient stepper motor control subsystems
ST Micro's Tom Hopkins describes how the L6470 programmable state machine based L6470 simplifies the implementation of multiple motor controls by integrating a digital control core with the driver IC to manage user-defined movement profiles with minimal loading on the main microcontroller.
Generate stepper-motor speed profiles in real time
Using a mid-range PIC microcontroller, this article describes a new algorithm for stepper-motor acceleration that allows speed profiles to be parameterized and calculated in real time.
PRODUCT HOW-TO: Choosing the right driver/controller combination for your stepper motor design
How to use AMI Semiconductor's ASSP ICs to achieve the right level of stepper motor controller/driver integration.
Designing a MCU-driven permanent magnet BLDC motor controller: Part 1
This three part tutorial provides the basics of implementing an MCU-based BLDC motor controller for use in automobile subsystems. Part 1: dealing with the basics.
Use micro-stepping techniques to smooth operation of step motors
This article details a micro-stepping design technique that improves the precision of the rotor movement and smoothes out the motion of stepping motors.
Stepper Motors Assist Adaptive Headlights
The latest adaptive front-lighting systems swivel headlight beams in advance of a vehicle's turning.
Designing a low-voltage motor drive
This tutorial outlines the basic rules for most effectively putting MOSFET gate-drive ICs to work for you
Electronic Control for One-cylinder Engines
Anti-pollution legislation around the world affects in particular the design for small gasoline engines. In order to meet future requirements, mechanical engine control systems have to be replaced by electronic ones. Freescale has developed a reference design for this application.
Open-Source Robotics and Process Control Circuit Examples – Part 2: Stepper Motor Controller
Learn more about prototyping complex robotic and control systems with this look at the design of the circuit and coding for a stepper motor controller for an autonomous submarine project from the “Open-Source Robotics and Process Control Cookbook.”
Embedded Systems Bookshelf
Excerpts
Embedded Books Reading Room
Bernard Cole's favorite links to book excerpts.
Reviews
Engineer's Bookshelf
Airport fiction blows. A look at books other engineers are reading and why you should read them, too. Recommend and write a review yourself. E-mail Brian Fuller.
Jack Ganssle's Bookshelf
A list of book reviews by Jack Ganssle, contributing technical editor of Embedded Systems Design and Embedded.com.
Max's Cool Beans
Clive “Max” Maxfield, the editor on Programmable Logic DesignLine, often writes about interesting books.
Products
New TI motor drivers for stepper and brushed DC motors lower RDSon more than 60 percent
Texas Instruments Incorporated (TI) has expanded its DRV8x motor driver family with eight new devices supporting up to 5 A for higher-current bipolar stepper and brushed DC motors.
Integrated driver ICs with high current capability offer space reductions in stepper motor designs
ON Semiconductor has launched two new integrated driver ICs that will drive high current motors with reduced component count and board space in stepper motor based applications.
ON Semi extends current range, flexibility for stepper motor designs
ON Semiconductor has extended its bipolar stepper motor control family to include two Serial Peripheral Interface (SPI) versions of a motor driver capable of peak currents up to 800 mA and for use with an external microcontroller for added flexibility.
Stepper motor unit with integrated motion control
The PANdrive PD-140-42-SE mechatronic unit from Trimanic contains a motion control element in combination with a 42 mm stepper motor (NEMA 17).
Device controls stepper motors with limited burden on MCU
LSI Computer Systems Inc.(LSI/CSI) has developed a low-cost precision stepper motor controller designated LS7290 that is designed to control two-phase bipolar stepper motors or four-phase unipolar stepper motors with minimum burden on the host microcontroller.
Enhancement to stepper motor increases design flexibility; emulates brushed-motor operation
AMI Semiconductor added enhancements to their family of single-chip stepper motor driver and control ICs. The new features include a facility for running stepper motors at a continuous velocity and an automatic start function which allows a stepper motor to start automatically when powered up.
|
