Table of contents
Abstract
Lead screw linear actuator driven by a Trinamic stepper motor and Analog Devices motor controller. This is an update in the "Start a Movement" design challenge.
Project
Intro
This linear actuator subsystem uses the Analog Devices TMC5272-EVAL Kit and Nema17 Trinamic stepper motor to create a robust general purpose lead screw linear actuator.
It is a short update but a lot of work went into it.
System Description
The linear actuator uses 2 guide rods to ensure the motion is linear and the mounting plate has no rotation.
The lead screw is captive in 2 pillow block rotary bearings that can withstand thrust forces if needed.
The stepper motor is connected to the lead screw via a flexible coupling which prevents undue stress of the motor bearings.
The 3D printed chassis is designed to ensure all components are located accurately in the proper locations, with the wooden base stiffening the whole subsystem.
The moving mounting plate has a series of mounting holes to accommodate different application peripherals.
Video - Assembly and Demo of the Linear Actuator Subsystem
Discussion
It is always tense when waiting 8 hours to try out a 3D print to determine if it works. The actuator chassis required meticulous measurement and design work to make sure it worked on the first try, but it was still nerve wracking because maintaining sub millimeter tolerances in a 3D print is pretty tricky. This chassis is within 1 millimeter of the maximum print width of my printer, which also has risks with build plate adhesion. Fortunately everything worked perfectly - it is a great feeling when things work this well. I still have some work to do to get the software cycling the way I want, but the main thing for this blog was to get the linear actuator hardware built and working.
3D Print STL files:
Next Steps
- Design the connector brackets and print them
- Design the chuck assembly and build it
- Program and test the connector tester motor control
- Program and test the thread tapping motor control
Links
- Project Blog 1 - Unboxing
- Project Blog 2 - Connector Tester Electronics and Firmware
- Project Blog 3 - Linear Actuator
- Project Blog 4 - Rotary Actuator
- Start a Movement Design Challenge page
- Analog Devices TMC5272 page
- TMCL-IDE page