Bluetooth LE connected rowing machines offer users performance insights and training data


WaterRower’s S4 Performance Monitor and ComModule employ Insight SiP ISP1907-LL module—based on Nordic’s nRF52811 SoC—to deliver wireless connectivity to fitness app

Anglo-American fitness equipment manufacturer, WaterRower, is employing Nordic Semiconductor Bluetooth® LE wireless connectivity in its rowing machine performance monitors to provide users with ‘real time’ access to motivational programs and data-driven incentives to train smarter and keep fit.

The WaterRower rowing machines are manufactured from a selection of sustainable hardwoods, and, unlike traditional fan or magnetic resistance machines, harness the power of water to provide smooth and even resistance and a realistic rowing experience in both sound and feel. The company’s ‘S4 Performance Monitor’ can be mounted to the rowing machines and displays a range of time, distance and intensity metrics.

Plug and play performance

The new S4 Performance Monitor integrates Insight SiP’s ‘ISP1907-LL’ multiprotocol module based on Nordic Semiconductor’s nRF52811 SoC. Earlier generation S4 Performance Monitors can be retrofitted with the ‘WaterRower ComModule’ that simply plugs into the back of the monitor and also integrates Insight SiP’s ISP1907-LL module. The inclusion of the Nordic-powered module in both the new S4 Performance Monitor and WaterRower ComModule provides Bluetooth LE wireless connectivity to the ‘WaterRower Connect’ iOS and Android app. From the app the user can review their metrics and workout history as well as be guided through more advanced workouts via an optional subscription service.

Several of the tools made available by Nordic were critical in reaching design targets
Chris Footner, WaterRower

“WaterRower is designed to replicate the experience of rowing in a boat, and is as close to being out on the water as you can get in the comfort of your own home,” says Chris Footner, Project Design Manager, WaterRower. “While the design has kept its core features for many years, connectivity has become an essential part of modern fitness equipment which made the Insight SiP module based on the Nordic SoC an ideal solution for the next generation of our products.”

Insight SiP’s ISP1907-LL is an ultra-miniaturized module based on Nordic Semiconductor’s nRF52811 multiprotocol SoC. The fully integrated module is offered in an 8 by 8 by 1 mm package size with a built-in antenna and is designed for space-constrained applications. The nRF52811 SoC combines a powerful 64 MHz, 32-bit Arm® Cortex® M4 processor, with a 2.4 GHz multiprotocol radio featuring 4dBm output power with -97dBm sensitivity (at 1Mbps in Bluetooth 5 mode), and 192 kB Flash memory plus 24 kB RAM.

The S4 Performance Monitor is powered by replaceable AA batteries, providing an active user more than 200 hours or over a year of use between replacement, thanks in part to the ultra low power characteristics of the nRF52811 SoC in the ISP1907-LL module. Exceptionally low energy consumption is achieved using Nordic’s sophisticated on-chip adaptive power management system.

Development tools made simple

“Several of the tools made available by Nordic were critical in reaching design targets, for example the addition of OTA [over-the-air] updates to maintain our devices in the future,” says Footner. “Together with a full feature IDE [Integrated Development Environment], this made development a more pleasant experience.

“Of all the solutions we have tried in the past, Nordic out-does everyone with its in-depth datasheets, SDKs and reference designs. Within minutes we had demo firmware loaded into our prototype hardware ready to test.”