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Teen creates phone charged by exercise

12 Oct 2021

Clara, from USA, built the innovative ‘Hermes’ shoe that charges your phone as you walk

The shoe encourages people to exercise and increase their step count by charging their phone at the same time - improving mental health and creating renewable energy! The do your :bit judges loved Clara’s idea and could see this solution working in the real world.

‘Hermes’ uses piezos, located under the insert of the shoe. A piezo tile allows you to harness energy when you push down on it. The energy created by walking is directed to a circuit outside the shoe and then to a battery pack. After you have finished walking, you can use the energy stored in the batteries to charge your phone.

Clara used the BBC micro:bit to report of the number of steps taken and energy created by them. She also programmed it to include games that would motivate teenagers to become more active.

Clara’s device is the winning entry in the do your :bit category for 8 to 14-year-olds in North America. She aimed to provide a solution related to Global Goal 3, Good health & well-being.

Clara explains how her device works

The do your :bit challenge is an annual competition which sets young people the challenge to innovate and design solutions relevant to the impacts of the Global Goals that are meaningful to them.

The ‘Hermes’ shoe

The ‘Hermes’ shoe



I chose to tackle this problem because I noticed that many teens in my community would rather sit around playing video games instead of going outside and being active.

Clara, winner, 8 to 14-year-olds in North America. 

Children and young people innovating with technology

The do your :bit challenge adds social purpose to digital learning and allows students to apply their digital skills to real world solutions. All projects and lesson resources are available for free and entries can be submitted into two age-range categories, 8 to 14-year-olds and 15 to 18-year-olds. 8 to 14-year-olds can submit either a paper prototype or working micro:bit solution.

Read about all of this year’s winning entries.

The next do your :bit challenge opens in early 2022, you can find out more about the challenge and access Global Goals project resources and lessons here.

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