Analogue, Mixed Signal, LSI


IMUs that carry machine learning burden

29 April 2020 Analogue, Mixed Signal, LSI

Designed for use in a wide variety of consumer and industrial applications, STMicroelectronics’ 6-axis iNEMO inertial measurements units (IMU) feature an embedded machine learning core (MLC) to offload the burden from the host processor. Machine learning is an application of artificial intelligence (AI) through which a machine can learn, by itself or in a supervised way, without explicit programming. It provides a system the ability to automatically learn and improve from experience without compromising the accuracy of the data collected.

The machine learning processing capability allows for moving some algorithms from the host processor to the IMU (inertial measurement unit). The IMU would therefore only consume less than one hundredth of the MCU (microcontroller) power used for the same typical tasks. The MLC is designed to run in a highly power-efficient manner and provides accurate results in the shortest possible time. A meta-classifier is also available to further enhance data accuracy in specific cases.

Developers of applications using sensors can thus benefit from the advantages of machine learning by creating their decision trees (using large data sets and high processing power) and having them run on an optimised MLC in the same sensor device.

Decision trees can be created and updated much faster using machine learning compared to explicit programming when appropriate data sets are available. The machine learning processing capability allows moving some algorithms from the host processor to the IMU. For typical tasks the IMU would consume 0,001 times the power of an MCU used for the same task. This is a key enabler for ultra low-power edge-computing. iNEMO IMUs with MLC can be configured to run up to eight decision trees simultaneously and independently, giving added flexibility to developers.

The LSM6DSOX contains a 3-axis accelerometer and 3-axis gyroscope and tracks complex movements using the machine learning core at low typical current consumption of just 0,55 mA to minimise load on the battery.

The consumer-grade LSM6DSRX contains a 3-axis accelerometer and a 3-axis gyroscope with extended full-scale angular rate range up to +/-4000 dps.

The industrial-grade ISM330DHCX comes with 10-year product longevity assurance and is specified from -40°C to 105°C, with embedded temperature compensation for superior stability.

Intelligent sensing with iNEMO inertial measurement units

iNEMO IMUs are built around three blocks, as shown in Figure 1.


Figure 1. iNEMO IMUs are built around three blocks.

The built-in sensors (accelerometer and gyroscope) filter real-time motion data before sending it to the computation block where statistical parameters defined as ‘features’ are applied to the captured data. The features aggregated in the computation block will be used as input for the third block of the machine learning core.

The decision tree evaluates the statistical parameters and compares them against certain thresholds to identify certain situations and generate results sent to the MCU. The machine learning core results are the decision tree’s output results which include the optional meta-classifier.

Building your decision trees,

iNEMO IMUs offer a wide range of design possibilities for developers by allowing them to create their own embedded machine learning algorithms and to build the best decision tree for their application.

Figure 2. iNEMO-based decision tree.

1. Collect data

The first step is to collect a representative set of data for the motion-related application being modelled. Examples of physical parameters include acceleration, temperature, sound, pressure, magnetic field, depending on your application.

2. Label and filter data and configuration features

Once the data is collected, a label is assigned to each statistical data pattern associated with an identified outcome, e.g. ‘jogging’ or ‘failure mode’. The computation blocks, i.e., the filters and features, can then be configured. The features are statistical parameters computed from the input data (or from the filtered data) in a defined time window, selectable by the user based on the specific application.

3. Build the decision tree

Use a machine learning tool for data mining tasks (such as Weka, Rapidminer, Matlab, Python), to generate settings and identify limits in the sample data to build a decision tree which recognises the type of motion data to be detected.

4. Embed the decision tree in the MLC

Weka or similar tools then generate a configuration file that is uploaded into the sensor and you are ready to go.

Operating mode: process new data using a trained decision tree

Finally, when the device is programmed, the machine learning core results can be processed using the defined, trained decision tree in your application. Developers can also get support and exchange ideas in the MEMS and Machine Learning and AI community page on the STMicroelectronics website (www.st.com).


Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

NXP has expanded its MCX A Series
Altron Arrow AI & ML
NXP has significantly expanded its MCX A Series of Arm Cortex-M33 microcontrollers, doubling the portfolio with six new families aimed at industrial and IoT edge applications.

Read more...
Surviving the extremes: Understanding shock and vibration in MEMS sensors
Altron Arrow Editor's Choice Test & Measurement
By considering factors such as mechanical headroom, damping, and system-level robustness, designers can ensure that the chosen sensor not only survives, but performs reliably over time.

Read more...
Exploring Bluetooth Channel Sounding
Altron Arrow Telecoms, Datacoms, Wireless, IoT
NXP has enabled BCS on the MCX W72 multi-protocol wireless MCU, which supports Bluetooth Low Energy 6.0, Thread, Zigbee, and Matter.

Read more...
Dual-band Wi-Fi 6 companion module
Altron Arrow Telecoms, Datacoms, Wireless, IoT
The SimpleLink Wi-Fi CC33xx family of devices from Texas Instruments are dual-band Wi-Fi 6 companion modules enabling engineers to connect more applications with confidence.

Read more...
Power module enhances AI data centre power density
Altron Arrow Power Electronics / Power Management
Microchip’s MCPF1525 power module with PMBus delivers 25 A DC-DC power and is stackable up to 200 A.

Read more...
High-performance linear regulator
Altron Arrow Power Electronics / Power Management
The TI TPS7A57-Q1 is an automotive-grade, high-performance low-dropout linear regulator, engineered for precision power delivery in noise-sensitive systems.

Read more...
Quad RF ADC/DAC for wideband transceiver design
Altron Arrow DSP, Micros & Memory
The AD9084 from Analog Devices integrates a quad 16-bit RF digital-to-analogue converter with a maximum sampling rate of 28 GSPS and a quad 12-bit RF analogue-to-digital converter.

Read more...
Collaboration to explore 10BASE-T1S SPE
Altron Arrow Telecoms, Datacoms, Wireless, IoT
The collaboration between Microchip and Hyundai aims to evaluate and promote the adoption of advanced in-vehicle network technologies leveraging each company’s strengths.

Read more...
High-performance processing for cost-aware industrial IoT
Altron Arrow DSP, Micros & Memory
STMicroelectronics has expanded its industrial processing portfolio with the new STM32MP2 series, a family of application microprocessors designed to deliver higher performance, advanced security and long-term reliability for cost-sensitive industrial IoT systems.

Read more...
Compact, durable and wideband wireless performance
Altron Arrow Telecoms, Datacoms, Wireless, IoT
The Taoglas Metal Stamped MPA Series of antennas is engineered to meet the growing demands of modern wireless devices that require high performance in increasingly compact form factors.

Read more...









While every effort has been made to ensure the accuracy of the information contained herein, the publisher and its agents cannot be held responsible for any errors contained, or any loss incurred as a result. Articles published do not necessarily reflect the views of the publishers. The editor reserves the right to alter or cut copy. Articles submitted are deemed to have been cleared for publication. Advertisements and company contact details are published as provided by the advertiser. Technews Publishing (Pty) Ltd cannot be held responsible for the accuracy or veracity of supplied material.




© Technews Publishing (Pty) Ltd | All Rights Reserved