---
title: "Weird Gadget Uses Your Knee Motion to Charge Your Phone"
description: "A new lightweight knee brace generates electricity as people walk around, potentially charging medical devices or wearables."
date: "2019-07-19"
modified: "2019-07-19"
authors:
  - name: "Dan Robitzski"
    link: "https://futurism.com/authors/danrobitzski"
url: "https://futurism.com/the-byte/gadget-knee-motion-charge-phone"
categories:
  - "Energy"
  - "Science & Energy"
tags:
  - "energy"
  - "the digest"
  - "wearables"
---

# Weird Gadget Uses Your Knee Motion to Charge Your Phone

![A new lightweight knee brace generates electricity as people walk around, potentially charging medical devices or wearables.](<https://futurism.com/wp-content/uploads/2019/07/gadget-knee-motion-charge-phone.jpg>)
*\<em\>Image: Gao et al. via API\</em\>*

## Pumping Up

A new lightweight knee brace could extract energy from a person's person's gait to charge medical devices, wearables, or even potentially a phone.

The 0.7-pound device, [described in research](<https://aip.scitation.org/doi/full/10.1063/1.5098962>) published Tuesday in the journal *Applied Physics Letters*, reportedly doesn’t make it noticeably harder for people to bend or straighten their knees, meaning it could help people capitalize on [their own motion](<https://futurism.com/building-the-soldiers-of-tomorrow-the-army-just-got-bionic-knees>) as much as possible — and, perhaps, eliminate the need for charging consumer electronics.

## On The Go

The Chinese University of Hong Kong scientists who developed the knee brace believe that the device could be used to continuously power people's medical devices or to make sure that hikers' devices don't run out of juice when they’re stuck far away from a power outlet, [according to *New Atlas*](<https://newatlas.com/knee-motion-energy-harvesting/60634/>).

For now, the project is still in the proof of concept phase, so there's no indication of when a commercial version might hit markets or how much it might cost, though *New Atlas* reports that a [similar device](<https://newatlas.com/pizzicato-knee-joint-energy-harvester/22933/>) developed seven years ago was expected to cost around $16.

**READ MORE:** [Wearable device harvests energy from bending of the knee](<https://newatlas.com/knee-motion-energy-harvesting/60634/>) \[*New Atlas*\]

**More on knee braces:** *[Building The Soldiers of Tomorrow: The Army Just Got Bionic Knees](<https://futurism.com/building-the-soldiers-of-tomorrow-the-army-just-got-bionic-knees>)*

## Author
Dan Robitzki is a senior reporter for Futurism, where he likes to cover AI, tech ethics, and medicine. He spends his extra time fencing and streaming games from Los Angeles, California.

### Author social links  
[Twitter](<https://x.com/danrobitzski>)