Meet Ghostwriter, a haunted AI-powered typewriter that talks to you

By | December 14, 2022
Ghostwriter understands what you type and can automatically write responses using OpenAI's GPT-3.
Enlarge / Ghostwriter understands what you type and can automatically write responses using OpenAI’s GPT-3.
Arvind Sanjeev / Ars Technica

On Wednesday, a designer and engineer named Arvind Sanjeev revealed his process for creating Ghostwriter, a one-of-a-kind repurposed Brother typewriter that uses AI to chat with a person typing on the keyboard. The “ghost” inside the machine comes from OpenAI’s GPT-3, a large language model that powers ChatGPT. The effect resembles a phantom conversing through the machine.

To create Ghostwriter, Sanjeev took apart an electric Brother AX-325 typewriter from the 1990s and reverse-engineered its keyboard signals, then fed them through an Arduino, a low-cost microcontroller that is popular with hobbyists. The Arduino then sends signals to a Raspberry Pi that acts as a network interface to OpenAI’s GPT-3 API.

When GPT-3 responds, Ghostwriter noisily types the AI model’s output onto paper automatically.

Examples of Ghostwriter's typewritten output, which comes from GPT-3.
Enlarge / Examples of Ghostwriter’s typewritten output, which comes from GPT-3.
Arvind Sanjeev

GPT-3 is an AI large language model trained on millions of books and websites that statistically predicts which word is most likely to occur after being fed a prompt, which includes text typed by the user on Ghostwriter’s keyboard. Depending on the input, GPT-3 can function like a chatbot or complete whatever text you feed it, including assisting with writing tasks or composing poetry.

While experimenting with the machine, Sanjeev realized he needed a way to control the creative “temperature” and response length of GPT-3, so he added two knobs and an OLED status screen just above the keyboard. Sanjeev also gave the machine a dramatic new gray, cream, and orange custom paint job.

Sanjeev first teased Ghostwriter on December 1, but it’s been months in the making. “The idea for Ghostwriter came in early 2021, inspired by Rob Sloan’s Sci Fi writer,” Sanjeev wrote on Twitter, “but it was difficult to squeeze time from my full time role at @Lumen_world, so I have been slowly spending my weekends working on this.”

Part art project, part artisanal hack, Sanjeev wants Ghostwriter to make a statement about the relationship between humans and AI.

“I wanted to create a mindful intervention that allows you to take a moment to breathe and reflect on the new creative relationship we are forming with machines,” Sanjeev wrote. “The calm meditative interface of a vintage typewriter takes away all the digital distractions and takes us on an emotional journey through paper and ink.”

For more information on how Sanjeev created Ghostwriter, check out his full development thread on Twitter, which includes videos that detail the construction process.