As part of the activities of the BSL, the team are developing a new range of electronic nose/gas analysers based on a range of different in-house and commercial gas sensor technologies. The WOLF (or Warwick OLFaction) electronic noses are the latest of these. Importantly, as these instruments are designed and developed in-house, it allows a high level of freedom allowing the instruments to be tailored to a specific application. We also have developed a wide range of commercial system. Currently there are 3 different series of these electronic noses, some examples of these are shown below.
WOLF Series 1 Analyser
These are small/portable units that are fitted with the latest in miniature gas sensors. Their purpose is for environmental applications and therefore, fitted with additional sensors to give an indication of the total quality around a person. This includes light (including UV), sound, temperature and humidity, as well as measuring total VOC (Volatile Organic Compounds), toxic inorganic gases and carbon dioxide. These units are battery powered and can last up to three days on a full charge. The units communicate through an Android app to a mobile phone/portable device, to give a real time reading of environment around the wearer.
The first generation unit was designed to be a similar size/shape to a smart watch. It included an integrated microcontroller, sensors and a Bluetooth BLE chip for communicating with the user. An overview of the system is shown in the figure below.
The second generation unit included a carbon dioxide and used a integrated microcontroller and Bluetooth module. This second generation was slightly larger and was designed to be tied to a bag or belt and carried with the user. This also sent information to the user via there mobile phone and collected location information allowing a map of environmental quality to be created. An example of this unit is shown in the figure below.
The third version of this unit is currently in development and will have a wider range of sensors, with improved functionality, and be based on a "clip-on" solution.
WOLF Series 2 Analyser
The series 2 analysers are designed for indoor or environmental monitoring solutions. Though they can be battery powered, they are predominantly designed for plug in applications and for monitoring over weeks or even months. The units are designed to have a wider range of sensors to those found in the Series 1 units. They also contain sensors of a higher specification and a particle sensors that would not fit in the series 1 solution. They have been used on a wide range of environmental and agricultural applications. A photo of the generation 1 unit is shown in the photo below. In this unit, a metal case has been used, with an OLED display to give an indication of readings. The unit has a LoRa module for communication, but also has a SD card for applications where RF communication is not possible. This unit has also been linked to a website, where online data from different units can be observed.
The second generation unit was designed for rougher environments and was fitted with rubber boots.
These units were designed for transport applications where the unit is placed in a container (or similar) and allows the environment to be monitored over the period the items are transported. In this case, the unit is battery powered and can last a few months on batteries. A photo of this unit is shown on the below.
WOLF Series 3 Analysers
The WOLF 3.1 & 3.2 Analysers are small more portable systems that can be taken to site, but are still main powered. The WOLF 3.1 system is fitted with a GC-metal oxide detection system, where pre-separation occurs in the GC column, followed by chemical interrogation using an array of metal oxide sensors. It is fitted with a fully integrated fluidic system, touch screen interface and real-time display.
The WOLF 3.2 is still in development, but uses optical gas sensor approaches to identify breath based bio-markers of inflammation. We expect the system to be ready in late 2016.
WOLF Series 4 Analyser
The WOLF Series 4 is a fully integrated electronic nose, containing:
- 4 Series - Desktop electronic nose
- Array of Electrochemical and Optical gas sensors
- Fully integrated control and drive electronics
- Environmental control hardware
- Integrated flow control
- Custom software interface written in National Instruments LabVIEW
- Easy to use and simple graphical interface
- Exports to common software analysis platforms
This instrument is already in use for both medical and agricultural applications.