Reliability and Continuous Improvement - CiES

Non-Contact Fuel Level Measurement

Recently we ran across an article in the Cirrus Owners Magazine  - Cirrus Pilot 

The article talks about the Continuous Improvement Process that Cirrus Aircraft utilizes in its aircraft design and production to improve reliability.

This article it discusses the complete paradigm change CiES made to aircraft fuel level measurement and Cirrus Aircraft's customer satisfaction with our non-contact fuel measurement technology.

As the article states - CiES Brought a Whole New Approach to Aircraft Fuel Level.  

An approach that changed fuel level reliability, so significantly, that it is no longer necessary to question your aircraft fuel level indication.

Take Your Fuel Level Indication to Un-Charted Territory and  Embrace the Reliability of the CiES Non-Contact, Magnetic Field, Fuel Level Solution

5000 Aviation Fuel Level Senders

After two years of production we have crossed a major milestone.

There are 5000 CiES Inc Fuel Level senders in the field or more appropriately, in the air.

What does that mean for our customer base or our potential customer base?  

The CiES Magneto Resistive Fuel Level system is proven and a good solution for fuel level measurement in a variety of applications.

We have proven the concept in what may be the harshest environment for fuel level measurement - aviation.  By proving ourselves in the aviation world we literally can take this method anywhere.


Our quality is phenomenal - out of the 5000 units in the field we have yet to take one out of service.
   
Can you say the same for your fuel level solution?

A Tale of Two Aircraft or Adventures in Aviation Fuel Level

Opportunity

We had been supplying OEM Fuel Quantity Indication Systems to Cirrus Aircraft G3 and G5 aircraft for a year with great success and we had obtained a Supplemental Type Certificate to retrofit this system to legacy Cirrus G3 Aircraft.  As we had the STC for the Cirrus it was only a small change to include the G1 and G2 model aircraft into the mix.  Generally Cirrus Owners had indicated that the G1 / G2 aircraft had better fuel reporting than the G3 brethren,  however we knew that the technology used by these early fuel sensors would eventually fail and without an OEM business and obligation,  the prior vendor was free to raise pricing to support this limited production.   We smelled an opportunity.

So we jumped feet first in retrofitting early Cirrus Aircraft.   The first indication we had that something was amiss was from a retrofit owner, he reported that the system looked good, but no comment on the accuracy of fuel level information.  This report stood in stark contrast to our experience on the retrofitted G3 and new G5 aircraft where fuel level reporting was deemed to be a notable highlight.  We had another customer install - same result - Gee it looks great, but no comment on accuracy in reporting.   I had heard about issues with the original G1 / G2 fuel level, but I attributed them to the potentiometer technology used to report fuel level.

We still felt we had the best system out there and we sold one more G1/G2 kit.   This owner was not so blasé about the accuracy - he noted and documented where the system was showing inaccuracies over his fuel totalizer system.   We had his calibration data from the Cirrus Service Center and his report that he lost 5 gallons every time he switched tanks.   We were confused - our system seemed to be able to leap tall buildings and burn through steel - inaccuracy in reporting was not something we had seen in the several years it took to develop our fuel level sensor.

Discovery 

So we set up the test tank with his calibration data, and started to run tests - the system performed flawlessly for us - it reported the same volume going up or down as we had initially found with calibration.  So what gives -  We had notated that aircraft structure prevented the Inboard fuel sensor (there are two in each wing for this aircraft  Inbd and Outbd)  from reaching it's full travel - and we set this limit up with a plexiglass box and tried the recalibration again.  Same result - nearly flawless recording, however we did notice one thing - when we depressed the Inbd sensor slightly by 1/4 inch or so we saw a 5 gallon decrease in fuel volume.

The Smoking Gun

We delved a little further - the sensors are actually located in separate tanks - one inbd of the other - the inbd tank (Collector) being much smaller connect to the outbd tank (Main) with fuel lines.

So with fuel being drawn out of the inbd tank the level in that tank must go down 1/4 inch.   Well was this true in the aircraft - we had reports for our system and the prior vendors loosing 5 gallons when that wing tank was selected.  We knew that it was consistent - if you depress the outbd sensor - the change is progressively smaller and not uniform.  Depressing the inbd sensor  invariably gave a 5 gallon decrease each and every time,  as long as some amount of measurable fuel was present in the main tank.  We asked the question "Could this tank level be effected by fuel pump suction"   So we modeled the system confirmed it with a little computational fluid dynamics,  Sure enough  5 gallons

So why 5 gallons - remember these sensors are in separate tanks see right - but in combination they measure the total fuel volume.  When the inbd sensor goes down due to a level change locally in it's smaller tank volume - this amount is subtracted from the larger main tanks -  a quarter inch in a 3 gallon tank is peanuts - a 1/4 inch in a 40 gallon long tank is well - 5 gallons.   The logical reason the manufacturer used the collector tank for the inbd location of the sensor,  is that this location is the best place to measure zero fuel level or the level of fuel just above the unusable amount.

How Do We Fix It.  

As we started our work on replacing aircraft fuel sensors in the field - we noticed a lot of subtle bends in the float arms used to optimize the travel on the 60 degree arc potentiometer cards These potentiometer cards are used in legacy fuel quantity systems.  We started looking carefully at what this was doing for the sensor, and it was all about geometry or in other words   How do you get the most bang for your buck with 60 degrees of potentiometer travel and 60 discrete data points - one per degree.  As an example Beechcraft Bonanza goes from least accurate at a full tank to most accurate as the tank drains, this is actually true of a few Cessna Aircraft as well,  It's what tends to happen in a small town.   

So why is this true - well - Float sensors have a few limitations -
First and foremost the float has to float Second as the float swings through an arc it goes from most sensitive at about 45 degrees above horizontal -- to least sensitive
at horizontal --  back again to more sensitive again at 45 degrees below horizontal -

This is a typical Sine function for those who remember trignometry  - and this is especially true for float sensors, as increasing fuel is the measured as the sine of the angle the float makes with the measurement system.   So these subtle bends in legacy fuel senders were making use of this fact to optimize their reporting capability.

We what if we bent the arms in a similar manner - could we can get the same result,  a fuel level output biased to be more and less sensitive as required.   We had not crossed that idea, as our patented sensor system  had a 180 degree travel limitation and 1000's of arc data points.  The CiES fuel quantity system due to the ability to render small changes into a discrete output,  accuracy due to geometry was not needed.  Given that - could we utilize geometry for a similar but opposite benefit - could we make the inbd unit less sensitive at the top of the collector tank and mask the small change brought about by fuel being sucked into the engine.  Time to run a few numbers.  It worked on the spreadsheet  - worked being a relative term -  it is less sensitive to change at the top of the tank, so out of a 5 gallon change we were now at 3 gallons  - not quite good enough.  OK this logic seems to offer some potential - what if we made the main outbd tank sensor more sensitive, trying to capture a subtlety in level.    Well in this combination,  less sensitive collector and more sensitive main tank  got down to just under the magic 2 gallon change.

Testing

Initial CiES Installation 

Time to run a few tank tests -  Eureka - the results from the spreadsheet matched the test tank data.  Excellent - time to document the revised sensor and cut metal for TSO senders to replace the ones in the field.

The Graph at the right shows the before condition of the aircraft.  You can see that the aircraft is in climb as both sensors are below the totalizer.  On the G1/G2 aircraft the senders run for/aft  - this tends to accentuate the discrepancy as the senders are real excellent angle indicators.

Notice that the right tank is nearly identical - gauge and totalizer prior to the update.  However the left tank shows a combination of fuel level error caused by the fuel draw and induced by climb.   I suspect that the fuel flapper valve in the left collector tank is sticky or there is a constriction in the line.

Conclusion 

Well we are waiting for a cross country flight to get a real assesment - However preliminary flights and taxi tests demonstrated that the results did carry over to the aircraft.   But as in all things aviation - you really want to see how this performs in the field.

First Report - Owner has flown the aircraft down to 20 gallons a side -- the system is accurate  and it matches the fuel remaining on the owners dip stick.  The fuel level change is in the range of 1 gallon when the tank is selected. 

It looks like we have taken a problem and turned it into an opportunity to demonstrate our capability - that's really what we are all about.

Talk with us - let us know the problems you might be experiencing in fuel level reporting - whether you have an Aircraft, Boat, RV, Truck  -

We solve problems with fuel level  - 

CIES Introduces a Fuel Level Sender for the LPG/Autogas Market.

CiES Fuel Sender in the SAE 4 Bolt Pattern  

We are pleased to be adding another sender platform.  

This platform is designed for the LPG / Autogas vehicle market but is also applicable to stationary LPG tanks or refrigerated trailer tanks.

This is an exciting new development for CiES as our patented technology is getting recognized by industries outside of aviation.  

The anisotropic magneto resistive technology employed by our fuel sensor system is simple and effective.  It is free of trace wear, hysteresis, vibration, temperature effects  and simply reports an accurate fuel level in any condition.

In aviation our technology has been a recognized success and hailed as a true innovation by the our OEM partners and their customers. 

Contact us to find out if we are developing a solution for your industry or application. 

Anisotropic Magneto Resistive - The future of fuel and fluid level detection

A major milestone occurred in 2011 -  the first commercially successful application of Anisotropic Magneto Resistive (AMR) technology applied to fuel level sending.    

We made our technological introduction a critical test for the sending unit as we choose to apply this sender to the most popular GA aircraft built.  It was a gutsy move to use aviation as our launch vehicle, but by all measure and after two years of flawless performance, we can say that this methodology for measuring fuel level has been overwhelming success.

The CiES Fuel Level Sensor is a magnetic, non-contacting angular position sensor that converts rotary motion of the float arm into an electrical signal.
This signal provides an accurate fuel level measurement and enables reliable Multi-Function Display or Fuel Gauge readout.  

Our compact, modular design utilizing the familiar SAE 5 bolt mounting allows a wide range of applications and our calibrated output signal compensates for component and assembly variations.  Our unique design using our patented AMR technology enables dependable performance and durability.


The CiES Fuel Level Sensor's linear output - either Frequency, Voltage or PWM Current Mode  is directly proportional  to the position of the float in the tank.  The we derive this location by the measurement of the magnetic field direction.  This method  allows for wide mechanical tolerances and sensor placement.  Just like a compass in your hand - no matter where or how you move the compass, it will continue to point North - our sensor continues to point at the float.

Noncontact performance is made possible by state-of-the-art  programmable Anisotropic Magneto Resistive (AMR) technologies. Rotating magnets generate a voltage with a paired sine wave response signal.   The sensor operates in a combined linear region of this  sine wave response signal.

Benefits 

• Low cost with electrical interface that powers and reads AMR effect output signal
• Modular and common interface help achieve competitive cost
• Can be easily modified to meet specific customer requirements
• Protection against contamination and fuel exposure
• Lower drive current minimizes system power consumption
• High resolution output signal with low hysteresis for improved system performance

Typical Applications 

The CiES Fuel Level Sensor is ideally suited for a wide range of aviation, automotive, heavy equipment, commercial vehicle, rail in-tank applications for Gasoline, Avgas, Jet A, Propane, Alcohol & Flex Fuel blends.  The non contact measurement method is immune from attack from any sulfur based, water based or solid contaminates.  This method of fuel measurement allows for a single fuel sender  to be applied to a wide variety of fuel types, including different fuels utilized in the same tank, providing the identical output response.

Performance Advantages

The CiES Fuel Level Sensor features a proven technology that has been used in high volume absolute position sensor applications, like brake by wire, throttle and accelerator positioning, for more than 10 years.

The non-contacting design of the sensor maximizes product life by eliminating fuel level signal deterioration due to contact wear, resistive ink failure or dendritic growth.  Our low current draw with high resolution output signal may be calibrated for the angular travel of a specific application and allows us to  compensate for any assembly or tank variations.  

Universal Fuel Level

Universal Fuel Sender

When we started out to re-define fuel level in aviation we looked at every aspect of what was causing present sender systems to fail.

We then broke that down into three basic concepts that needed to be addressed:

1. The sending unit had to accurately report the position of the float in the fuel tank.
• We used our Patented AMR Sensor Solution
• Exceptional Accuracy
• High Reliability
• Non Contact  - Fuel or liquid intolerant 
2. The sending unit had to be built to aviation standards.
• We utilized aerospace materials and tight tolerance machined parts
• Aerospace Coatings
• TSO Designation - built and tested to an Aerospace Performance standard
3. The communication to the cockpit of the fuel level had to be fool proof
• We used a digital frequency output
• Easy communication, no connection or wiring issues
• Similar communication to fuel flow
• Easy to diagnose 

We created a phenomenal solution for aviation - In 1 1/2 years of delivering this product - we have yet to have an unscheduled removal from an aircraft - 

Over 2500 units in the field and not one failure.  

We produce this unit for the highest production single engine aircraft.

We measure Avgas, Jet A and Alcohol De-Ice fluid with the same unit.

We addressed the aviation aftermarket with a display partner Aerospace Logic to produce an  fuel level display unit that would accept our frequency input.    Aerospace Logic has approvals for their display in all types of GA Aircraft.

We addressed and solved a perplexing problem in aviation

 Accurate and Reliable Fuel Level

In creating news in the aviation field  we have generated a lot of  interest in our product. 

Fuel Sending Units are Universal 

Applicable to all fuel tanks

in any industry or vehicle 

same SAE Bolt pattern 

We are expanding our market 

The new sending unit design needs to have optional outputs:

1. Digital Frequency - proven in the field - exceptional clarity
2. Ratiometric Voltage - a  0 to 5 Volt solution
3. Current Output - simulating a variable resistance  

With this configuration we can accommodate all cockpit or instrument interfaces  - we even left a pigtail to accommodate existing connectors 

Talk to us about any fuel level sending issue 

Fuel Level Senders - Automotive

Fuel level sending has been the providence of electrical resistance since somewhere in the 1930's when electrification of the automobile hit full stride.  The Ford Model A used a very clever sight gauge so that you actually saw a liquid representation of fuel level - neat design but expensive.

http://www.facebook.com/Fuellevel

Resistance Level worked very well and was easy to understand  -  X Ohms Full - Y Ohms Empty

Simple

And then suddenly somebody decided to add alcohol -  to fuel -

Methanol and ethanol contain soluble and insoluble contaminants.[5] Halide ions, which are soluble contaminants, such as chloride ions, have a large effect on the corrosively of alcohol fuels. Halide ions increase corrosion in two ways: they chemically attack passivating oxide films on several metals causing pitting corrosion, and they increase the conductivity of the fuel. Increased electrical conductivity promotes electrical, galvanic and ordinary corrosion in the fuel system. Soluble contaminants such as aluminum hydroxide, itself a product of corrosion by halide ions, clogs the fuel system over time. To prevent corrosion the fuel system must be made of suitable materials, electrical wires must be properly insulated and the fuel level sensor must be of pulse and hold type (or similar). In addition, high quality alcohol should have a low concentration of contaminants and have a suitable corrosion inhibitor added.

So if you turn to any car chat blog (ANY CAR CHAT BLOG)  -

Failed fuel level sensors are driving OBD II cars to the shoulder.

So we need to find a replacement  Smiths (Stewart Warner, VDO, Veglia, Et al) in a Pulse and Hold fuel senders - Not compatible 

We are producing  a patented new non-contact fuel level sensor.

We are applying the sensor presently  to aviation (aircraft, rotorcraft) - In aviation we don't have alcohol,  but we can't put wires in the tank - something about electricity and fuel

Aviation  requires - what cars - all cars using Alcohol mixed fuel need - A non contact fuel level sensor

It is also helpful in this environment 

Fuel Level Sensor Under Test

We use a new concept in our sender called Magnetoresistance - certain materials change resistance in the presence of a rotating magnetic field and they can do this from as far as 3/8" away actually from the dry side of the tank.

Most of us see this everyday in the compass on our smartphone

There is no pivot or contact resistance,  so the float can be smaller and the range can be larger (fuller fulls and emptier empties)

Neat thing is that the  output of this sensor  can mimic a resistive sensor

Hey if you find this interesting let us know

scott.philiben@ciescorp.com

Local Recognition - Cascade Business News

Cascade Business News 

Pamela Hulse Andrews

If the recent Made in Redmond Tour organized by Redmond Economic Development Inc., (REDI) is any indication, Redmond is on a fresh path to promoting its economic opportunities. In addition, its new City Manager Keith Witcosky and interim Airport Manager Bob Noble bring innovative perspectives to expanding Redmond’s economic potential.

Last month REDI invited community members, business owners, educators and government leaders to tour several unique businesses. Four companies were showcased that manufacture unique products in Redmond including Key Technology, CIES, McConnell Labs/Light Elegance and Central Oregon Truck Co.

Jon Stark, manager of REDI, says the companies selected are successful examples of the progress that has been made in economic development. REDI and Economic Development of Central Oregon (EDCO) have collaborated extensively with city, county and state leaders in cultivating a fertile climate for business to be successful in Central Oregon.

While acknowledging the success of current Redmond companies, REDI is looking at soon-to-be newly zoned 465 acres of industrial land, some private and some airport owned, that will include parcels from 30-50 acres for attracting larger scale industrial and manufacturing companies.

Redmond may not be as sexy as Bend with its appealing high end retail and boutique shopping, numerous restaurants and cultural events, but companies wanting to move to our region will find Redmond a very favorable place for reasonably priced site and development costs, a competent workforce, affordable labor costs for their business and transportation access including a world class airport.

Redmond gets high marks, too, for paving the way for development, resolving zoning issues and mitigating important site or expansion matters.

.......

Another Redmond company,  CiES Inc provides reliable fuel sensors for aviation. CEO Scott Philiben says, “CiES employs mechanical and electrical engineers and high quality skilled workers. We make about 3,000 devices a year and have recently added six jobs to the Redmond economy. We will grow at 50 percent per year for the next several years.”

CIES has improved on a patented fuel sensor technology and produces systems that are designed to provide exceptional fuel level accuracy in the harshest conditions imaginable. The company is successful in the world aviation market and is leading the technology for additional liquid fuel markets in the U.S. and Europe.

These companies, along with the entire Central Oregon region, depend on the Redmond Airport, some for shipping products, all for business travel. With a steady increase over the years in passenger flights and upgrades and expansion of facilities the Redmond Airport has positioned itself to be the central hub for transportation in Central Oregon.

Redmond’s new city manager lured Nobel, an experienced airport manager, to help him guide the direction of this significant ecnomic asset. Nobel has more than 18 years of experience in numerous public aviation leadership roles across Oregon.

Given the importance of the airport to the region’s growing economy and transportation needs, Nobel has been charged with working on long term airport goals including assessing the current airport environment, identifying critical issues and developing the processes for implementing changes.

Witcosky is looking ahead and says he wants the Redmond Airport to become known as the best airport of its size in the nation. “That means it will be the preferred choice for commercial air carriers and general aviation clients based on the best services, infrastructure and facilities of any airport of similar size in the country. Clients will recognize this value by investing through leases and other contracts which allow the airport to be a self-sustaining and continually improving community asset.”

Redmond has a vision and summarized by its new city manager: “Our vision is that aviation, aerospace and other traded sector industries continue to invest and cluster around the airport. Partners such as Redmond Economic Development Inc. (REDI) and Economic Development for Central Oregon are working with us to create jobs and attract private sector investment.”