This week’s EYE ON NPI (video) is buggin’ out – with TDK Invensense’s SmartBug Multi-Sensor Wireless Module! Much like our recent product, the Adafruit CLUE, we’re seeing more and more chip companies create ‘showcase’ hardware boards with a large number of sensors, and a wireless setup for quick demos. TDK did a particularly nice job on this one, it’s both adorable and powerful!
From the product description page:
This module combines six sensors, a powerful wireless (BLE) MCU, seven algorithm-driven features, and a rechargeable battery all in a small ladybug enclosure. It also comes with the option of an add-on board that includes a Wi-Fi module, an SD card slot, and an ultrasonic sensor from TDK.
It is the go-to module for quick and easy access to reliable and smart sensor data. The data from each sensor and algorithm can be accessed out-of-box without the need for any programming, soldering, or extra modifications. This makes it a perfect catalyst for IoT product developers, algorithm developers, and sensor data enthusiasts to better understand real application signatures, environment variations, and multi-sensor/algorithm behaviors.
I like that they went with a cute shape for this board, it’s a plastic ladybug, which is easy to open up with 3 simple screws. Inside is a custom PCB with micro USB power/data, a Nordic nRF52840, 290mAh battery, and a whole mess-load of sensors. There’s also an expansion port on the side, which you can use to plug in more sensors like a ToF range finder, two buttons, SD card storage and an ESP32 WiFi module.
The nRF52840 is the main processor, and provides the sensor connectivity, USB interface and of course Bluetooth LE – it’s one of our favorite processors, and hey it could be reprogrammed to run CircuitPython, which would be super cool if someone made a board definition.. hint, hint.
In the SmartBug are five sensors that cover motion and environment:
- ICM-42688 triple axis accelerometer plus gyroscope
- ICP-10101 barometric pressure
- CH101 ultrasonic time-of-flight range sensor
- AK09940 triple-axis magnetometer
- SHTC3 humidity + temperature sensor
The real star quality of this product is the surprisingly well-done Windows 10 application. As you may know, Windows 10 added native BLE support, so it’s possible to write desktop apps to communicate with sensors. Usually these sorts of dev board evaluation apps are kinda clunky, but this one is rather nice! You can find the app in the app store, so there’s no popups warning you about running unknown apps. Once installed, you can run it, select BLE as the transport and connect in a jiffy. There’s on on/off switch, the board will power down after inactivity and will auto-connect when picked up.
The app has many nice features. The plotter is the first one we tried. It’s exactly how you’d imagine, with selectable data rates – you can have multiple sensors at once.
Next we tried the activity monitor – this one implements tap detection, plus pedometer/activity sensing using the IMU. What’s nice is that since this board is wireless – you can put it in your pocket to test the pedometer!
Finally, we looked at the HVAC demo that uses the pressure sensor to detect when filters in an AC unit need replacing. I liked the realistic product demos here, for example I didn’t realize that was a use case for pressure sensors.
TDK / InvenSense is famous for their IMU’s – they’re used in a wide range of motion-activated video game systems and VR such as the Nintendo Wii and Oculus Rift. So it’s no surprise they have a really sweet IMU demo showing of their fusion algorithms. These are now often built into the chips themselves, running a proprietary Kalman-like filter that will spit out quaternions or Euler angles. Again, this is a great demonstration of the wireless connectivity – you can pick up the ladybug and twist and twirl it around to see the rock-stable fusion output.
A few last things before we wrap this up – there’s also a really handy debug console (ha!) that gives you useful information like the BLE characteristics being queried. If you don’t have BLE, you can use the built-in USB interface option which uses a Serial Port (we couldn’t find documentation for the serial protocol, but you could sniff the data passing by to create your own library). Also, there’s lots of documentation for using the built-in SD data logging, which could be handy for long term data collection.
All in all, it’s a nice bit of kit, at a good price! You can pick up a SmartBug at Digi-Key today, they have plenty of stock, and will ship it to you same day (https://www.digikey.com/