Sensors Expo 2009 - A World of Interconnected Sensors

Beth Wozniak, President of Sensing and Control, Honeywell Automation and Control Solutions, gave a thought-provoking keynote on Wednesday titled, A World of Interconnected Sensors. She talked about the “Internet of things” - the notion that with advances in wireless and the acquisition of sensor information, coupled with autonomous controls, connected devices can become as pervasive as the internet. The future may hold a wide range of applications that have not been imagined. Beth noted that estimates of the wireless sensing market are $5-10 billion, including aerospace, transportation, industrial, healthcare, and other applications. She mentioned that wireless is a great advantage for undeveloped and emerging economies with limited wired infrastructure.

IEEE 802.15.4-based ZigBee

 

The MRF24J40MB is Microchip’s second 2.4 GHz Radio Frequency (RF), surface-mountable transceiver module. The new module offers customers extended range for distant-node communication, while eliminating design and certification costs, reducing risk, and enabling quick time to market.   The chip module adds +20 decibels per milliwatt of transmit power using an integrated power amplifier and -102 dBm of receive sensitivity via the integrated low noise amplifier. More transmit power allows designers to expand the range of their IEEE 802.15.4-based ZigBee or proprietary-protocol wireless networks. Microchip’s newly certified ZigBee PRO protocol stack provides another option for IEEE 802.15.4-based wireless networks using Microchip’s PIC Microprocessors MCUs. The combination of Microchip’s ZigBee PRO stack, the MRF24J40 transceiver radio or transceiver modules, and any of its 16-bit PIC24 MCUs or dsPIC33 DSCs forms Microchip’s ZigBee PRO Compliant Platform, as certified by the ZigBee Alliance.

 

In addition to providing the ZigBee protocol stacks, designers who don’t require interoperability or large-node networks can save on certification and microcontroller memory costs by utilizing Microchip’s free MiWi™ and MiWi P2P IEEE 802.15.4-based protocol stacks. All of Microchip’s ZigBee and proprietary stacks are available for download today from its online Wireless Design Center.

 

ISM Band

 

Microchip Technology also announced the expansion of its wireless portfolio with the new MRF49XA Sub-GHz transceiver radio. The MRF49XA covers the 434/868/915 MHz unlicensed Industrial, Scientific and Medical (ISM) Radio Frequency (RF) band, which is ideal for low data-rate, low-power embedded wireless applications. By retaining compatibility with its existing suite of development tools, Microchip makes it easy to integrate this new Sub-GHz transceiver with any 8-, 16- or 32-bit PIC® microcontroller, enabling cost-effective designs for a wide range of, bi-directional, short-range wireless applications, such as remote controls, remote meter reading and home security/alarms.

 

The MRF49XA transceiver radio is available on a PICtail™/PICtail Plus daughter board for easy integration with the 8-bit PIC18 Explorer and 16/32-bit Explorer 16 modular microcontroller development boards. The 434 MHz Daughter Board (part # AC164137-1, $39.99 for a two-pack) and 868/915 MHz Daughter Board (part # AC164137-2, $39.99 for a two-pack) are both available today at www.microchipDIRECT.com.

www.microchip.com/Wireless

 

Inductive Touch Sensing Analog Front End (AFE)

 

Microchip Technology also announced the MCP2036 Analog Front End (AFE) for inductive touch-sensing applications. Inductive touch sensing’s fundamental operating principles enable it to work through a front panel, such as plastic, stainless steel, or aluminum. The technology also works through thick gloves and on surfaces where liquids are present. Designers wanting to learn more about implementing touch sensing into their applications can visit Microchip’s online touch-sensing design center. www.microchip.com/mtouch

Micropelt demonstrated their Power Generation Thermoelectric (TE) power generation based on using a temperature differential to generate voltage. Micropelt thermogenerators produce voltages in the range of 0.5 – 5 Volt depending on actual temperature differences on some 12 square millimeters of footprint – sufficient energy to drive a wide range of low-power wireless applications including remote sensors, data loggers and small actuators.   Micropelt TE-Power BOLT is an good example of the technology that can power wireless and remote sensors, data loggers and other low power devices without batteries.

Perpetuum demonstrated wireless sensors powered by their energy harvesting technology. Perpetuum has been the leader in vibration energy-harvesting with its microgenerator, capable of generating enough power to enable the reliable transmission of large amounts of data. Vibration energy harvesting is the simple notion that mechanical vibration can be transformed into useful electrical power. Perpetuum’s vibration energy harvesting microgenerators are based on a highly optimized magnetic circuit coupled to a mechanical resonator. This arrangement successfully transforms the kinetic energy of vibration into electrical current.

Futek demonstrated USB connected load cell, torque, and pressure sensors. Data acquisition using these sensors can be done with any computer with a USB connection. FUTEK offers a USB210 Kit to convert existing sensors to a USB output.

Encoder-On-Chip

 

Renishaw upgraded its 13-bit magnetic rotary encoder-on-chip - clamed to be the world's first with 8192 counts/rev, to higher speeds, better noise control, improved time delay and accuracy, plus unique performance tailoring capability. The enhanced RLS AM8192B increases operational speeds to 38,000 rpm at 13-bit resolution (60,000 rpm at 12 bit), while a simple software interface allows designers to choose optimum settings for applications, as well as providing a HEX setting file for easy upload.

 

The simple non-contact design of separate magnet and ASIC eliminates wear, friction, and the need for seals and bearings, assuring long-term reliability. The ASIC contains an array of Hall-effect sensors that generates a voltage when exposed to the magnetic flux field. Sine and cosine voltage outputs vary with magnet position, which the ASIC's configurable internal interpolator converts to a range of binary and decimal resolutions. The ASIC is able to cancel magnetic interference, permitting operation in areas of high external magnetic fields. 

 

Encoder resolution is configurable using an external EEPROM while the Hall sensor array is already factory-trimmed for optimum performance. The absolute angle position value can be accessed though an SSI interface. Relative changes of angle position are simultaneously output as incremental A QUAD B encoder signals at up to 8192 counts per revolution. Simultaneous SSI and incremental capability enables the 13-bit AM8192B encoders to be used for both motor commutation and velocity control at the same time.

 

RLS magnetic sensors/encoders

 

Renishaw demonstrated a new generation of position encoders for harsh environments that provide the same output signal and wiring as a traditional potentiometer, with virtually unlimited life, no wear and resistance to environmental contamination such as dirt, grease, oils and dust. They are 100 percent solid state devices, eliminating shock and vibration issues, and offer non-contact, reliable operation.

 

At just 14 mm tall and engineered for extreme service, the LM13 linear magnetic encoder is ideal for tight spaces and tough applications too dusty, dirty, greasy, or destructive for optical encoders. The LM13 has user selectable resolution up to 250 µm and handles operating temperatures from -10°C to 85°C.

 

Also featured were the industry's first 13-bit magnetic rotary encoder providing 8,192-count positioning resolutions and operating speeds to over 30,000 rev/min, and the LM10 linear magnetic encoder delivering resolutions to 1 µm at 4 m/s in applications too dusty, dirty or destructive for optical encoders. Rugged solid-state, non-contact magnetic design provides reliability against extreme temperatures, vibration, high acc/dec rates, and pressures. Low cost, compact size, multiple formats, and design simplicity enable use in a wide range of industries.

www.renishaw.com