Wire Bender
Fall 2018
This project was developed in response to a prompt to research and create a machine on the technical equivalence of a 3D printer as part of may favorite undergraduate course on Rapid Prototyping and Physical Computing taught by François Guimbretière.
Motivations
A product designer rapidly prototyping on some idea needs to get a feel for the dimensions of an object they are considering making. He or she could 3D print or laser cut a part, but that is often time consuming and expensive, and its degree of precision is often unnecessary in the early stages of prototyping.
Instead, the designer can take up a piece of wire, and in near real time have a 3D wireframe of their design to hold, observe, and then iterate on. Once done with this preliminary iteration, the wire used can be re-straightened for future use in another iteration or project. This process is suitable for early design iterations, but building wireframes quickly and relatively accurately is no trivial task. Ideally, a designer would be able to take advantage of the flexibility and abstractness of wireframe models without sacrificing accuracy or speed.
Outside of the world of product design, there is an artistic community centered around constructing sculptures out of wire. While there are valid reasons to continue sculpting wire art by hand, there is certainly a place for automated wire sculpting as well. Given the difficult nature of dealing with complex wire sculptures by hand, an automatic wire sculptor could serve as a tool that helps artists iterate on designs as well as potentially expand the set of things artists are able to make in general.
Design
We set out to build a 3D wire bender that meets the needs of both product designers and artists. We started with a simple design that focused on constructing 3D wireframe models both quickly and accurately. Though there has been some previous work in this field, we sought to improve on the non-industrial, DIY use case. None of the existing wire benders we found support wire with a gauge as small as we used, so our bender design is theoretically capable of processing models with a higher level of detail than other wire benders available.
The basic construction of the wire bending machine contains 3 primary parts:
- A feeder that pushes the wire through the machine,
- a bender which bends the wire at specific angles,
- and a 3D rotator to move the bender around the axis of the wire.
In order to interact with the bender, I developed a web based application to that sends instructions to the RedBear (Arduino compatible board) controlling our wire bender. The general flow of using the prototype is as follows: manually feed a piece of wire into the machine, then either draw something on our interface that converts 2D drawings into instruction sets for the machine, or click on one of the buttons that corresponds with a preset 3D model instruction set, and then clock “Bend It!”.
To read more about design decisions and process, read the full paper.
A screenshot of the web application I developed to send instructions to the wire bender wherein a user could either draw a 2D shape, or select a preset 3D shape to bend.
A rendering of the Wire Bender's 3D rotator assembly.
Components
- A high torque 360 degree servo motor
- A 12V 20Ncm stepper motor
- A 2.5V 1.26Nm high torque stepper motor
- A 1.2A DC Stepper Motor Driver Breakout Board
- A 12V 5.5mm throw solenoid
- A RedBear Arduino compatible board
- Three 3-D printed motor brackets and a cone for the end of the feed tube
- A steel pipe
- Two pipe sleeve bearings
- Two aluminum base mounted shaft support
- Two laser cut acrylic gears
- Multiple laser cut acrylic boards for the bending head
- A laser cut acrylic board for the base plate
- Various nuts and bolts
