Electronics

Tele Servo Bender emulates a lap steel sound using servos

Tele Servo Bender emulates a lap steel sound using servos
The servos are controlled by a cabled foot pedal via an Arduino running custom code
The servos are controlled by a cabled foot pedal via an Arduino running custom code
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The first test model, with a single string, analog servo, Arduino and breadboard
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The first test model, with a single string, analog servo, Arduino and breadboard
A homemade CNC was used to route the cavities in a Telecaster-shaped body
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A homemade CNC was used to route the cavities in a Telecaster-shaped body
The A, D, G and B strings pass through the saddle screws on their way to the servos
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The A, D, G and B strings pass through the saddle screws on their way to the servos
Close up of the servo assembly
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Close up of the servo assembly
The circuitry of a keyboard sustain pedal was stripped out and replaced with a magnet and a continuous ratiometric hall effect sensor for smooth bend control
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The circuitry of a keyboard sustain pedal was stripped out and replaced with a magnet and a continuous ratiometric hall effect sensor for smooth bend control
The servos are controlled by a cabled foot pedal via an Arduino running custom code
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The servos are controlled by a cabled foot pedal via an Arduino running custom code
The finished Tele Servo Bender
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The finished Tele Servo Bender
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Though mostly associated with country music, there's a pretty good chance that you've heard the sweet singing tones of a lap steel guitar in whatever modern genre floats your boat. OK, maybe not techno or electronica, but certainly blues, rock, jazz and folk music. Rather than gently stroke the six to ten high action strings of an electric lap steel with a glass or metal bar though, Dean Miller opted to recreate the sound using four servos controlled by a modified foot pedal array and an Arduino running some custom code. The result is pretty astounding.

Miller (aka gr4yhound) took around two months to develop and build the Tele Servo Bender in his spare time. He first tested his idea for a servo-activated detune using a simple setup of a spare neck bolted onto a piece of ply, the Arduino, an analog servo and a breadboard, before starting work on routing the cavities in a Telecaster-shaped body. He bought a cheap bridge and bored through the screws of the saddles to allow the A, D, G and B strings to pass through.

An aluminum mounting plate for the analog servos was cut using a homemade CNC, and the cavities containing the guitar pots and switches, and the one housing the servos, shielded to help reduce noise interference. The servos were lined up with the appropriate string, which runs over a 3D-printed pulling horn to control the speed and distance of the bend.

The finished Tele Servo Bender
The finished Tele Servo Bender

Miller stripped out the circuitry of a keyboard sustain pedal and installed a magnet and a continuous ratiometric hall effect sensor for smooth bend control. There's one pedal for each string. He says the easiest part of the build was the creation of the code for the microcontroller, which he's made available for anyone who wants to build their own Servo Bender.

As you can see and hear in the video below, the DIY project is so convincing that you can almost feel the jaws of lap steel players dropping as Miller runs through a few tasty licks.

Source: Dean Miller

servo bender

View gallery - 7 images
2 comments
2 comments
Chris DeBarge
Very cool device, though it is not emulating a lap steel, but rather a PEDAL steel. Keep up the fun work!
DonGateley
Awesome! Pretty it up and he'll sell tons of them. While he's no slouch, you gotta wonder what a guitar master could do with one. The sound could easily move into other genre's than country or gospel.
I expect to start hearing this on recordings.