Article
Breakthrough water meter for Master Meter
This article has been taken from The Gen newsletter - Autumn 2010.
The move towards a metered water supply by water companies around the globe has created a demand for a low-cost water meter register that can be read remotely, deliver an accurate, reproducible reading and will continue to operate, maintenance- free, for many years. By combining mathematical ingenuity and sound product development and engineering skills, Sagentia has satisfied that demand by producing a novel contact-free register – AccuLinx – for its US client Master Meter.
Master Meter, a leading Automatic Meter Reading (AMR) technology innovator and water meter manufacturer, initially approached us to design the gearbox and enclosure mechanics for a new water meter register based on a third party six-wheel encoder. The brief called for a register that could fit on a wide range of meter bodies, from small domestic units to street mains, and which could be used in different countries to record US gallons, cubic metres and cubic feet.
This, potentially, called for hundreds of different variants of the gearbox on the same meter body – an expensive solution due to the cost of injection moulding and tooling. By employing number theory developed in-house, we were able to demonstrate that gearboxes could be made from a set of just 17 gears which satisfied all the various gearbox permutations. By limiting the number of gear wheels, Master Meter was able to reduce its tooling outlay by 90 per cent which led to $ multi million savings.
Toward the end of the gearbox development project, we approached Master Meter with a proposition for an eight-wheel absolute encoder that would be based on an entirely new, Sagentia patented technology known as Gray Wheels.
Our proposition was driven by the growing market need for a cheaper odometer that could be ‘read’ electronically (using automatic meter reading technology). We also appreciated that the chosen system should not add friction or torque to the odometer – as this would lead to under readings and consequent loss of revenue. In practice, this called for readings to be undertaken using a non-contact technique.
For some time we had been exploring, in-house, different ways to improve on existing non-contact technologies. Our long track record in inductive sensors led to us developing the technology known as Gray Wheels. As with the previous gearbox development, ingenious mathematics lay at the heart of the technology – this time an error tolerant cyclic code system based on Gray codes.
The potential to develop a real breakthrough product was appreciated by Master Meter and a licence deal was agreed between the two parties. AccuLinx, the resulting eight-wheel, battery-free, absolute encoder, is non-contact and can be read remotely by third party AMR systems. In addition to readings for billing purposes, the system is also proving indispensible for leak detection.
AccuLinx is an absolute, as opposed to, incremental encoder. Should power be lost
or intermittent, or should the reading be taken in an electronically ‘noisy’ measurement environment, the exact position is always determined at each reading without moving the encoder. This class of encoder is therefore ideally suited to low power applications where high data integrity is paramount. In addition to utility applications, it is expected that Gray Wheels technology will find use in safety- security critical areas including medical, automotive and aerospace applications.
Our ability to understand the challenge set by Master Meter, from a fundamental mathematical and scientific perspective, coupled with sound pragmatic engineering and product development skills, led to a true advance in water meter technology. It provided a smoother, more effective route to market for Master Meter with a highly differentiated product within an established competitive landscape.