running shoe manufacturerDevelopment division

The Challenge of Building State-of-the-Art Smart Running ShoesThere are a lot of challenges in module development


Recent years have seen a surge in demand, chiefly in the sporting sector, for “smart shoes” fitted with IoT sensor modules that can record information on the wearer’s walk or run. However, the need to power these modules with large-sized, rigid rechargeable batteries means that in the case of most smart shoes on the market, the sensor module is not incorporated into the insole itself. Rather, the module is attached to the outside of the shoe, or space is made in the shoe sole to accommodate the sensor module. However, wearers of smart shoes complain that this causes them discomfort when walking. In response to this criticism, the client decided to develop a new smart shoe.


The Challenge of Making Sensor Modules Smaller and Lighter

Initially, the client decided that the sensor module had to be made lighter and more compact in order to resolve the discomfort of which users complained. The client looked into how this might be achieved. While it was possible to make the microprocessor, Bluetooth Low Energy (BLE) communication system, memory, and other components fairly compact, the lithium-ion rechargeable battery and charging connector could not be made any smaller. What’s more, the addition of the longer battery life and more advanced features that users wanted would make it necessary to increase the capacity of the battery, making the miniaturization of the module even more difficult.

Durability Hurdles

Battery size and capacity were not the only issues. The client evaluated several prototypes and experimented with thinner packages and the like, but encountered issues of durability whereby the impact generated when the wearer’s foot hit the ground would cause the battery to be instantly separated from the circuit board, or even snap in two. Committed to developing a high-spec sensor module that would not be noticed by the wearer, the development team gathered information on lithium-ion rechargeable batteries from around the world and considered many options. However, the client did not find a battery that satisfied their requirements.

Main Issues

  • While the client attempted to miniaturize the sensor module, it was unable to make the lithium-ion rechargeable battery or the charging connector any smaller.

  • The need to increase battery capacity to allow longer battery life and more advanced features made miniaturization even more difficult.

  • Thinner modules caused durability issues, whereby the impact of running would cause the battery to be separated from the circuit board or even snap.