TEMPERATURE REGULATOR FOR OVENS - FUSE - …€¦ · · 2001-09-12TEMPERATURE REGULATOR FOR OVENS...

EGO ITALIANA S.p.A. Demonstrator document for FUSE project: AE 24792

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FUSE Application Experiment 24792Dissemination / Demonstrator document

TEMPERATURE REGULATOR FOROVENS

Microelectronics applied to cooking saves bothmoney and power

AE number: 24792New Technology: MicroprocessorIndustrial sector: Electric Domestic Appliances (2971)Contact TTN: COREP


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Abstract of the Application ExperimentEGO Italiana SpA, a 250 employees company with a 30 MECU annual turnover,manufactures and sells electromechanical devices for white goods (thermostats, switches,hotplates, elements) since 1960The purpose of the AE (application Experiment) has been to develop a new electronictemperature regulator for domestic and industrial cooking equipment (such as ovens,hotplates, highlights plates, etc…), based on a fuzzy logic processor.The new FLTR (Fuzzy Logic Temperature Regulator) regulator controls a non-linearthermal behaviour by means of fuzzy rules and the control is especially aimed to saveenergy, and to improve the cooking cycles and temperature ramps, to reduce temperaturefluctuation during cooking operations and to improve the final user safety. The mostimportant advantage of the whole AE is that it enables the use of high power electronicappliances on simple 16A plugs instead of the heavy and rare 32A plugs that exist only inrelatively recent constructions.The fuzzy rules allow an easy software customisation of the regulator to be used in thevarious applications that can be produced by the equipment manufacturer. The fastturnaround time asked by our customers will be eased with such a product where simplereprogramming or new added ports enable us to react to the market demand very quickly.The currently produced EGO thermostat is electromechanical and operates on the liquid-expansion principle.The market share would be increased of 10-15% in 2-3 years. The economic break even forthe FUSE budget is estimated in less than 6 months. from start of productionEGO expects to reach a cumulated margin differential 7 times the total sustainedinvestment for the industrialisation in three years only of production..This proves how strategic is for EGO to move towards microelectronics.With this experience we intend to get the basic know-how to open to a range of electronicproducts applicable to cooking, washing, heating equipment and, to keep our leadership inthe market, we intend to promote a wider use of electronic control systems into the whitegoods industry in order to generally improve control performance, energy saving andsafety.Considering the overcoming of the internal barriers to the use of electronics, the improvingin the know-how of the company, and the concrete availability of the prototypes to showto the customers, we can consider the AE as a success.The total cost of the AE is 44 kECU and has been completed in 7 months.EGO is operating in the 2971 industrial sector but the results of this ApplicationExperiment might also be interesting for companies in the field of food & beverage (15) andwater supply and distribution (40).


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Keywords and SignatureKeywords: Temperature regulator, fuzzy logic, rules, knowledge base, marketconcentration, conservative management, domestic and cooking appliances,microcontrollerSignature: 2-01415601321-2-2971-2-29-I

1. Company name and address

E.G.O. ITALIANA SPAVia per Cameri, 1028100 NovaraITALYContact Person: Sergio GuzzettiPhone: +39 321 669811Fax: +39 321 669827E-Mail [email protected]

2. Company size

EGO Italiana S.pA. is the Italian branch of the E.G.O. group, based in Germany,one of the most important component suppliers for the white goods industryworld-wide 250 employees work in the plant located in Novara, of which 3 are electronicengineers.Turnover in 1997 was around 30 MEURThree persons represented the electronic experience inside the company. Two ofthem came from the silicon process sector and had experience mainly in wafertechnology. One of them is the head of the R&D department and the other is thehead of the electronics department. The third person is the designer whose onlyprevious electronics experience was the graduation work on analogue design. Withthese backgrounds, the AE found EGO Italiana SpA as a first user in themicrocontroller technology.

3. Company business description

EGO Italiana SpA develops, produces and sells electromechanical components forthe white goods market, both industrial and domestic. Components are controlsystems (thermostats, switches…) and heating systems (hotplates, elements stemgenerators, and grills).The company is especially focused on cooking (components for ovens, hobs, cook-tops, fryer) and washing (components for washing machines, dishwashers,sterilises) application.

EGO Italiana SpA is certified ISO9001.


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The manufacturing of the present products is mainly concentrated inside thecompany and just few subassemblies are subcontracted.The production of electronic boards will be subcontracted to third parties at thebeginning. Inside production could be strategic in the future for some products.

The products are directly sold to customers who tend to pass from monthly ordersto weekly or daily orders considering us as a link of their just-in-time system. EGOItaliana is reacting to these requests by shortening its cycle times.

Big efforts are made for service and a team of 3 people is engaged in problemsolving for customers when existing or new components by EGO Italiana SpA areintended to be used in new models of appliances.

The market is European and the main customers of EGO Italiana are the Italianwhite good manufacturers as Electrolux-Zanussi, Whirlpool, MerloniElettrodomestici, Smeg, Nardi, etc. Nevertheless EGO is strongly committed insatisfying the needs of all small customers, typically specialised in niche products,even with strong customisations of existing products.

Recently both big and small customers tend to transfer part of their know-how tothe component makers, due to the increased complexity of the appliances, thus thecomponent maker is requested to supply technological solutions beyond thecomponents themselves, as in case of the automotive market.

The FLTR development was carried out having in mind this general trend.

4. Company markets and competitive position at the start of the AE

4.1 Market description

The company delivers to European white goods manufacturer and 90% ofproduction is for the Italian market.The Italian market is constituted by big companies (Electrolux-Zanussi, Whirlpool,Merloni Elettrodomestici, Candy) and smaller companies who cover more than 50%of the European white goods market.

The total Italian market of thermostats for white goods is:

Business field Application Pieces/year(Millions)

EGO shareAbsolute(Millions)

EGOshare -%

Cooking Ovens +Cookers+ Hobs

4.2 2.2 52

Washing WashingmachinesDishwashers

3.81.2

1-

26-


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Heating Water-heatersBoilers

2.52.2

0.05-

2-

Industrialappliances

All 0.4 0.3 75

Smallappliances

All 2 0.15 7.5

Total 16.3 3.7

In each business field the traditional electromechanical thermostat covers todayabout 95% of the total market; 5 % is covered by electronic temperature regulators.

Two considerations are important in order to explain better the EGO Italianastrategy into this market:

The first consideration is that electronic devices for control of domestic appliancesare presently playing a very important role in the higher performance domain, butthe market forecasts from our customers state that electronic devices will have abreak-through in the middle level domain where the highest volumes areconcentrated. In fact in this market segment a kind of regenerative feedback isexpected since both the performance and the availability of electronics have apositive effect on the market itself.

The second consideration is that the market of components for white goods ispresently distributed among several companies, and they are all living aconcentration phase: in some years only three or four companies will survive bygrowing and having a wider portfolio of products.

Considering now the thermostat Italian market, the competitive situation is asfollows:

Company Pieces / year(Millions)

Share - %

EGO 3.8 23IMIT 4.6 28PRODIGY 0.8 5ATEA 0.8 5T&G 0.5 3CAEM 0.8 5COPRECI 0.7 4METALFLEX 0.8 5EMERSON 0.8 5Others 3 17

Total 16.3 100


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The average price of our electromechanical thermostat is 17 EUR with about 9% margin.This is certainly convenient with respect to most of our competitors

EGO Italiana, being market leader, is one of the candidates to win the concentration match.One of the most important conditions (because of the first consideration) is to besuccessful in the conversion to electronics.

It is worth noticing that the usage of electronics is recent in the white good industrialsectors.Digital electronic programmers are available for more advanced washing machinesAnd dishwashers only since 6 years.Application of electronics in cookers and electric ovens is far behind other industries sinceup to now electronic solutions more costly than any electromechanical one. ).Few competitors of ours are now able to produce electronic thermostats, but their pricesare not at all appealing at the moment,The reason is that the electronic temperature controllers have been realised till now using ananalogue approach which turned to be more expensive (30% more than theelectromechanical thermostat according to our estimatesMoreover it does not offer those flexibility features that are required by the equipmentmanufacturers and the final users.Being the electronic thermostat market only 5% of the total thermostat market the aboveconsideration is almost independent of the competitors present market share in theelectronic field. More important in order to be successful are quality, reliability and costsof the product and mainly the accordance with the customer’s expectations.Therefore, the AE is aimed at improving the competitive position of EGO Italiana in thethermostat for cooking business field. In a second step, thanks to the skills acquired duringthe AE, the other business fields will be attacked.

The background and the forecasted for the current electromechanical thermostat is shown inthe following graph

0

2000

4000

6000

8000

1994 1995 1996 1997 1998 1999

kEU

R

00,10,2

0,3

0,40,50,60,7

ME

UR

Sales

Margin


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5. Product or process to be improved and the reasons to innovate

The currently produced EGO thermostat is electromechanical and operates based on liquid-expansion. The hydraulic system - also called ‘diastat’ - consist of the sensor, the capillarytube, the diaphragm, and the expansion medium.When the sensor is heated up, the liquid expands through the capillary tube into thediaphragm where a working stroke is produced. The stroke activates a snap-action switch,which opens or closes the electric power supply circuit.Here is a scheme of the electromechanical thermostat:

The present product can be used for regulating the temperature of liquids, gases and solids.

• Temperature ranges:

rock

snap-action

mains

spindle

capillarytube

diaphragm

temperaturesensor

calibration nut

heatingelemen


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0°C - 40°C heating air, room-heating appliances;30°C - 110°C heating water, washing, boiling, saunas, heating systems;100°C -180°Cheating fat/oil fryers;50°C - 500°C heating air, electric cookers, ovens, heaters.

• Operational characteristics:

− the thermostat can drive mono-phase and 3-phase power line in a− single-, double-,three-, and four-pole configuration;− fixed temperature models;− continuous setting of control temperature with spindle models.

• Thermostat sensors:

− sensors are of different designs and sizes according to requirements of thevarious applications.

Approvals:− EGO Thermostats are VDE and IMQ approved. In addition approval-marks of

many other test authorities from other countries are available.

• Switching performance:

− 6A for each contact path at 240V;− voltage and power demand can be tailored to customer request..

The product to be improved is the group of electromechanical thermostats that typicallycontrols a domestic cooker with hotplates.

This thermostat has been sold successfully for many years and has been very appreciatedfrom our customers because of its very good reliability (more than 8000 hours mean time tofailure [mttf]), but now the company clearly understands that the market has new needs.

• First of all with the current electromechanic thermostat is not possible for the user tohave an electronic panel able to monitor the state of the heating plate (whether this ishot or cold) which means a lack of safety.

• Moreover none of the more modern cookers manufacturers accepts anymore to producean equipment which is not provided with a new electronic panel where the user can setcooking parameters and oven temperature through up-down pushbuttons and visualisethem on a display.

• Another key issue is power saving through a clever sharing among the different cookingappliances so that the consumed power stays below the critical 3 kW threshold..

We wanted to keep the cost advantage of having only a very simple temperature sensor anda control system which does not need to be too much accurate (5% accuracy is fairlyadequate).


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We planned to halve the price of the whole controller for our customers (the cookersmanufacturers) while keeping the same unit margin so to greatly increase our market share.and to get a leader position among the components suppliers for the white good industryWe understood that all these goals could only be reached making a technology jump andmoving to electronics

6. Description of the product or process improvements

The temperature regulator, which is the object of the AE, is aimed to control thetemperature of a simplified version of the application shown in the figure below. Thisconsists of a single heating plate (1.6kW, 230V) and a multifunction oven (2.4kW, 230V)which can be operated both separately and simultaneously. A Pt100 resistor is used tomeasure the oven temperature.The most important features of the new component are the following

• Very high flexibility of the control obtained thanks to a Proportional Integral (PI)control for the heating plate and oven temperature regulation

• Power sharing management using a fuzzy rules set for deciding on the optimum powersharing between the two appliances, with optimisation of power demand, whose limitis set at 2.8kW instead of the nominal 4kW.

This feature is very important, as it will allow selling cooking appliances in places wherethe power plugs do not exist, such as old constructions. This feature by itself will increasethe market of the new product that can be safely operated on low power plugs.Using a plate heating model, the user can obtain a control of the heating features of eachplate, with a far greater efficiency than the one obtained through the usage of a modularheating approach (switching a on bank of resistors with a rotary switch).Clients look for energy spare and the domestic appliance constructors will impose strictrequests in this respect to their component suppliers.

• New digital user interface made up of a very simple keyboard, LCD display, LED, andUP/DOWN pushbuttons.

According to the operated function (selected through the keyboard) the display can be usedboth for visualising the oven/plate set temperature or the cooking programmed timeA complete cooking appliance equipped with a single oven and 4 hot plates is shown in thefollowing figure.It has to be said that although the electronic solution and associated firmware have beenconceived for a complete equipment, the specific product that we plan to commercialisesincludes only one or two hot plates; this is due to our customers requests.


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Fig 1 Block diagram of the cooker

O

PI

T

P

F

G

R

R

R

R

s D S

C

T

P

I/O

Hotplates

Oven

SensorBus


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The new product is also very flexible. With a simple reprogramming of the microcontrollerand new connections it can be adapted to virtually all future products of the company.This capitalisation capability is among the biggest advantages of the project.

The user interface is represented in the figure below

User front panel

fig. 2

P: HEATING PLATE PUSH-BUTTON (LED1)F: OVEN PUSH-BUTTON (LED2)TIMER: TIMER PUSH-BUTTONTEMP: TEMPERATURE PUSH-BUTTONUP: SELECTED PARAMETERS UP ADJUSTMENTDOWN SELECTED PARAMETERS DOWN ADJUSTMENT

The block diagram of the realised electronic control board is shown in fig. 2. As you can seeall peripherals (keyboard, displays), push buttons are handled directly by the PICmicrocontroller. The only external circuitry is the front-end section of the board, where themeasured temperature is acquired and conditioned before it is processed by the micro via anon-board A/D converter.

OVEN FUNCTION SELECTOR

POWER RELAYSKEYBOARD


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fig. 2a

The newly introduced microcontroller technology will allow the following advantages

• Size reduction due to miniaturisation of the controller obtained thanks to theintroduction of microelectronics

• Increased flexibility (Thermal behaviour of the cooker and thermal characteristicparameters are software programmable according to the specification of the cookermanufacturer).

• User friendly interface which allows the final user (professional cook or housewife) tochange the cooking temperature or time very easily

• Maintained reliability with respect to the old product thanks to the unique board andthe controller/ power separation

• All these improvements are obviously transferred onto the cost which according to ourestimates should be about 60% lower.

It should in any case stressed again that the real added value of this innovation for EGOstems from the introduction into the electronic world which is considered strategic for thecompany to keep its leadership in the market.

7. Choices and rationale for the technologies, tools andmethodologies

EGO Italiana is new to use electronics in its marketed products and we think that thedevelopment of the fuzzy microcontroller is a smooth start, but that already means a veryhigh improvement of the performance and safety of its products.The market already offers examples of reliable fuzzy logic temperature controllers,although for applications other than white goods, (e.g. Omron) and therefore the risk of thisAE should not be too high.

Size reduction is an important requirement since the controller should fit in the cookerfront panel

The choice for a digital controller based on microcontroller implementation was suggestedby both the TTN and the Design assistance subcontractor. After a thorough discussion itwas clear also for EGO that traditional analogue control needed a very accurate model ofthe controlled system and this is not easy to implement for thermal equipment like ovenand heating plates.Analogue techniques are very critical when dealing with non linear feedback.

Moreover, those controls cannot be made easily customisable by the white goods maker.

Digital control systems, using traditional microprocessor, require a deep knowledge of thephysical phenomena that are part of the process in order to be able to express them by welldefined algorithms. This approach can be successfully used only in the case of PID


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(Proportional Integrative Derivative)controllers, or at least, with very simple non linearsystems.

Energy saving and safety control are the key features of the new FLTR and fuzzy logic hasbeen considered very robust from this point of view.An important characteristic of fuzzy controllers is their fast control recovery in case of astrong variation of the external parameters affecting the system.‘Safe if fail’ algorithms was widely used in order to control every possible dangeroussituation both for the final user and the control system itself.

Other more advanced technologies like FPGA or digital ASIC were discarded for thefollowing reasons:

• FPGA cost something more (at least 25%) are less flexible, require more hardware skill,and are justified neither for speed nor for complexity requirements

• Digital ASIC cost a lot more in the development phase, require a lot of design skill andcapability in using advanced CAD tools. Moreover is a very risky and stiff technologywhere errors cannot be corrected and most of NRE (Not Recurrent Engineering) costsshould be paid again in case of failure in the first development.

On the other the final cost of an ASIC component in large quantities is the lowestavailable, therefore we would reconsider this possibility in the future, once we havegained deeper knowledge and confidence with the electronic technologies, for furtherlowering our costs and gaining a further market share.The methodology followed in developing the software for the PIC microcontroller wasbased on an high level approach:

1. a block diagram behavioural representation of the control is produced, using thehigh level Simu-Link language which allows to describes the behavioural equationsof each block.

2. the block diagram can be easily simulated for different initial conditions soproviding a first level verification of the exploited algorithms and the set of rules.

3. from the Simu-Link description through the Microchip Fuzzy-Tech software theassembler can be easily produced for both the emulator (PICMASTER) and themicrocontroller.

Testing was carried out using the MPLAB simulator for a for a first level codeassessment and than directly on the target board with a logic state analyser

8. Expertise and experience in microelectronics experience of thecompany and the staff allocated to the project

The company has expertise in electromechanical technologies and no experience inelectronics.EGO is developing electromechanical thermostats since 1977 and has a good experience inpower handling, dealing with relays, power resistors transformers and rotary.Two persons were involved in the project at the beginning


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• A senior electronic engineer with 3 years experience was assigned the project managertask

• A young engineer will play the role of designer and will be trained and assisted by thesubcontractor.

The head of the electronic department also kept an eye on the project and the hiring of onemore technician was hired during the project progress

9. Work-plan and rationale

The timing diagram of the project development is reported below (

May 97 June 97 July 97 Aug 97 Sept 97 Oct 97 nov-97

Management & diss.

Specificat. & training

Design

Prototyping

Testing

Original Workplan

Implemented Workplan


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Work-plan

WP1 (Specification & Training) Concluded within the end of July (also the generaltraining on Fuzzy logic)

First User Definition of the requirements for the new componentSubcontractor1: Train the EGO staff• Deliverable Complete Specification document including:

• Functional Specifications• Hardware definition• Software definition• EMC and reliability definition

WP2 (Design) Concluded within the first week of October

First User: Participate in the development of the schematics and the softwaredevelopment through on job trainingSubcontractor1: Develop the schematics of the PCB, develop the microcontrollersoftware, give on job training to the first user

• Deliverable Complete Hardware and Software project including:• Interfaces, sensors, actuator choice• Hardware project• Software project• Software debug• Training on Fuzzy Logic

WP3 (Prototyping) Concluded within the third week of October

First User: Give the main rules for the PCB masterSubcontractor2: Develop the PCB master and manufacture the prototype

• Deliverable Assembling of the system including:• Prototype board• Hw/Sw review• PCB prototype development• Prototyping

WP4 (debug and testing) Concluded within the end of October

First User: Develop the testing procedure for the final PCBSubcontractor1: Assist in testing and debug phase

• Deliverable Final verification including:• Functional and electric testing• Variations identification


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• EMC and reliability testingWP5(Project Management and Dissemination) Concluded within the end ofNovember

First User: Carry out the management of the project, including project progress control,reporting and preparation of the dissemination material

• Deliverable Dissemination document including:• Flyer document• Demonstrator document

The work-plan is in agreement with the original one attached to the proposal (only thetiming diagram is different due the delayed start). Due to the delay in funds commitmentfor the last phase of FUSE and to some problems in defining the target market for the newproduct the design team was set up only at the end of May.This delayed the spec definition which ought to be delivered at the end of May.The first draft of the specifications was delivered at the end of June with about 1 month ofdelayThe extension of the development of the specification definition did not result as a plainwaste of time since some activity was also performed in the same period on the definitionof the electric schematic for the signal conditioning partDuring the first audit with the TTN, a time schedule revision was undertaken on 10/07/97.According to this new planning the activities to be performed after 15/6/97 wererescheduled and the milestones for the deliverables were changed according to the followingprogram.

A training, planned in the original proposal, on the fuzzy processor WARP was notattended for 2 reasons

1. A different micro (PIC) was selected for the development since the WARPmanufacturer did not assure a sufficient support

2. No suitable training course was made available from the WARP manufacturer

In the audit held in EGO on 15/09/97 it was decided to ask EC for a contract extension upto the end of November.

The delay (about one month) was due to both technical and organisational reasons.• As a first reason we had to cope with the non availability of an emulator

board for the targeted micro (WARP) and were forced to choose a generalpurpose solution which for economical and technical considerations was aPIC microcontroller by Microchip. This allowed also the best exploitationof the training offer from Politecnico of Milano since they had a lot ofexperience with this micro.

• The second reason was the impossibility of EGO technical staff (Dr.Guzzetti and Dr. Viglione) to fully commit to the FLTR development.The need to perform also the more traditional and day-by-day work (whichfor a company like EGO is mainly mechanic or electromechanical) hascaused slight delays, in the most important phases of the project execution.


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• The delay was contained thanks to the effort of the design assistancesubcontractor who gave a strong help even beyond the subcontractconditions. Also the fact that the company added some resources during thelast development phases helped in reducing the delay in the design phaseconclusion.

• There were unforeseen delays with the final prototypes provided by thesubcontractor. These delays were more to do with subcontractor internalissues than the time estimated.

The design work was partially subcontracted.The main effort of the company was spent in the design and testing phases, where a strongon job training was requested from the subcontractor.A young engineer was detached from the EGO plant and worked at the DAS premisesunder its direct supervisionA 4 days tutorial was offered at EGO personnel (3 persons) on the basic issues ofdesigning with microprocessors and later another 2 days course regarded the basic of fuzzylogic theory and design.

A table of the cost and effort sustained by the company and its subcontractor is reportedbelow

EGOEffort Persons/days)

DASCost*(kEUR)

FS**Cost*(kEUR

Task Planned Real Planned Real] Planned Real]

Management 10 21Specifications &training

22 30 2 2

Design 60 82 9 9Fabrication &Assembly

10 15 6 6

Testing 20 35 1 1Total 122 183 12 12 6 6

*DAS:Subcontractor1 (Design Assistance Subcontractor)** FS: Subcontractor2 (Fabrication Subcontractor)

The effort of the FU was even higher than expected since tour company wanted to acquireenough know-how to be able to deal with future projects almost independently.Therefore the EGO staff involvment in the software development and debug was higherthan planned at the beginning.The weight given to the project management procedures was also increased as far as theproject proceeded and this was reflected in the corresponding effort.

10. Subcontractors information

10.1 Subcontractor1: Design Assistance

The selection of the subcontractor for assisting EGO during the AE development was madefollowing the criteria listed below:


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• Deep knowledge of electronic design, both hardware and software• Good attitude in understanding project management rules and transmitting them to

EGO• Capability in offering training in both lecturing and on the job forms• Good understanding of industrial problems including organisational one• Some previous specific knowledge on the application and the product to be developed

Especially the last requirement was very hard to be satisfied, but we believed it reallyessential because the subcontractor had to understand thoroughly the system in which themicrocontroller had to be embedded.Luckily at the end we were able to find a subcontractor who could satisfy all our requestsand we obtained his assistance for:

- Choice of the most suitable microcontroller according to the defined specifications(input/output needs and requested interface features)

- Control board hardware design that means: microcontroller signal conditioning(amplification and filtering of the sensor output), output interface with the powerdelay drivers (SIPO shift registers and latches).

- Design verification using the electrical simulator Spice- Design and realisation of prototype PCB where the different features could be tested

and the performance measured.- High level verification of the fuzzy control laws, using advanced simulation tools like

Matlab e Simulink.

- Training on microcontroller software programming with experts in developingassembler programs in well-equipped labs.

- Development and debug of the fuzzy algorithms first on the emulator and in a secondtime on the prototype PCB with the possibility of a real time adjustment andcorrection of the software directly on the in system micro.

- Co-operation in the final verification phase and trimming of the control algorithmsonce the prototype board is assembled in the final target product.

In all these development steps we found the Design Assistance subcontractor quite skilledand his co-operation with EGO was considered very fruitful.We can recommend this design team for offering assistance to all companies who want todeal with a micro design for the first time

10.2 Subcontractor2: Fabrication subcontractor

We looked for a subcontractor able to provide us with the following services

• Assistance to EGO for the best engineering of the controller PCB (including the powerpart)

• Master of layout; placement and routing• Process 5 prototypes• Assembly of the electronic components• Volume production (When required)


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Indeed the last requirement was not so tight because production would have been decidedat a later stage, but according to Ego and its Design Assistance Subcontractor it would havebeen convenient for saving time if the production were carried out by the same companywhich had dealt with prototyping. In fact all testing procedure and tools could have beenset up once for all at the prototyping phase.At the end we selected as subcontractor a large PCB manufacturer with a good experiencein both developing well engineered prototypes and in dealing with production andassembly of boards in high volume.

10.3 Contractual IssuesThe usual procedures was used• An offer was requested and negotiated with the subcontractor• An order was issued where the specification list was taken as an annex• Payments where associated to the availability of the corresponding

deliverables

11. Barriers perceived by the company in the first use of the AEtechnology

EGO Italiana strongly wants to go to electronics for the reasons described above, but thestrategic decision has to face cultural, technology and other barriers anyway. This becauseof the way of thinking of electromechanical engineers who want the electronic products tobe developed with an electromechanical approach!.

Knowledge barriers:The lack of experience determined the first problems. The technology choices have beenvery hard to make and it took a long time to understand if to face the problem from ananalogue or digital point of view. The fuzzy approach was decided after months of difficultinvestigations.The subcontractors’ choice was difficult too, because it is hard to find a subcontractor whocan understand the industrial point of view and teach him how to define precisespecification for an electronic product.

Cultural and inertia barriers:EGO Italiana has a big expertise in electromechanical technologies but no experience inelectronic technologies.EGO Italiana, being ISO9001 certified, has an internal procedure for product development(addressed to its electromechanical products), but we found difficulties in adapting thesame procedure to an electronic product.The main problems in this sense have been:• choice of supplier: The EGO purchase office is used to deal with mechanic

component maker who typically work on specific drawings.and found difficulty is to get in touch with electronic components supplier (theytypically pass through distributors) and to discuss with them about prices versusvolumes or about delivery times. We had a superficial knowledge of the


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development cycle for an electronic product, but a very different thing is to workon it and we found many difficulties in following a formal project managementespecially during the software development.

• We faced also the problem that it is difficult for a mechanic company to let anengineer to deal only with electronic design problems. So we had frequent interruptsbecause ‘an engineer is always a high salary employee and we cannot waste his timein dealing with only one kind of problems’.

• Very critical was also the problem that the knowledge of the proper values ofimportant parameters belonged to old experienced electromechanical designengineers who are not very willing to share their experience with the youngengineers of the electronic design group.

Technology barriers:A very accurate model is needed to control the system and this is not easy to make and toimplement. Typically the ovens makers do not consider the thermodynamic model of theirproducts and so no theoretical approach was available.A big effort was spent in modelling the thermal behaviour of the heating plate thatconstitutes the basis for the operation of the electronic control system.Related to the problem above, the state space is difficult to be identified.The selection of the suitable micro was also a big problem for EGO since they had noacquaintance with the micro jargon and at the beginning they do not even understand themain differences between a traditional and a fuzzy approach.This lack of experience made EGO too much confident in the ST promiseswith the consequence of the troubles mentioned above

Financial barriers:The main financial barrier is the very high cost to build up and to maintain an electronicdesign team who is considered only as a cost until the new regulator will be produced andsold by the commercial department.

12. Steps taken to overcome barriers and arrive at an improvedproduct.

Knowledge barriers:Our experience is that the only way to overcome the knowledge barriers is practice. TheAE has been a good opportunity to make (or to be forced to make) practice.

Cultural and inertia barriers:The market already offered examples of reliable fuzzy logic temperature and this gaveconfidence in trying a new development.A systematic training was offered by the Design Assistance subcontractor to give acomplete view of the organisation of the electronic design.The engineers involved in the AE worked very closely with the subcontractor forengineering and fabrication and this has improved very much our ability to have relationswith the component suppliers. The purchasing department people will greatly gain fromtheir experience.


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A very tight control by the TTN also assured project management training along thedevelopment of the AE. The acquired skills about project management will be used toupdate the ISO9001 procedure for product development.The EGO design engineer has often worked at the Design Assistance subcontractorpremises where he could not be interrupted. The result we are having from the AE is topersuade people that when an engineer deal with only one problem the probability to getgood results rises up.Two technicians have been hired to help the design engineer in the most simple task and toassure continuity to the day by day work.The experienced electromechanical engineers have been forced to work with the electronicdesign group by the management. The use of Fuzzy logic helped a lot by allowing an easyconversion of their experience into the fuzzy rules. The good results obtained from the AEwill make the rest.

Technology barriers:It was chosen a Design Assistance subcontractor with an established experience indesigning and training on fuzzy logic for industrial process control.On job training was the right answer making one of the company engineer to be deeplyinvolved in the design task together with the Design Assistance subcontractor.The experience of the Design Assistance subcontractor is such to suggest us how to definethe fuzzy set of rules and make the right choice for the target micro.The alternative choice of the PIC was the consequence of the early perception of the willfrom ST not to support WARP which allowed to contain the delay in the whole softwaredevelopment and debug process.

Financial barriers:Without this new electronic shift the EGO market share could decrease because of theabove discussed reasons. This situation forced the EGO Italiana management to invest andto continue to invest into the electronic department.The whole company evolution will benefit from the expected market results of the newproduct.

13. Knowledge and experience acquired.

A very effective training was offered to EGO by the DAS technical staff.Short courses were given on the following topics:

♦ Design criteria and development flow for an embedded application♦ Criteria for the choice of the microprocessor♦ Fuzzy logic and set of rules definition♦ Software implementation of fuzzy algorithm

With this courses and the continuous on job training during all phases of the ApplicationExperiment we gained experience with fuzzy logic fundamentals, fuzzy logic possibleapplications, fuzzy processor programming and fuzzy control system developing.Other experiences acquired concern the components choices an the boards layoutdefinition.


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The acquired skill during the product development will constitute the basic know how fordeveloping fuzzy control systems dedicated to other applications in the white good fieldsuch as washing machines, dishwashers and catering systems.We have learned how to define functional and electrical specifications of the electronicsystems.Some basic notions on microcontroller architecture, general features of the PIC family,fuzzy logic fundamentals were transferred by the Politecnico di Milano Universitysubcontractor.We have learned how to define the hardware interface and how to implement the fuzzyalgorithm using the internal architecture and the microcontroller software. Then we havelearned how to define the state space and the set of rules for the specific design problem.We have used and learned a dedicated emulator for the PIC microcontroller.Most important we learned the electronic language and are now aware of the mainproblems you have to face when dealing with this technology for the first time.We can say that our major goals have been reached :

- Acquire knowledge on designing with embedded systems in our specificsector

- Understand how to set the specification for a digitally controlledthermostat

- Develop testing and debug procedures for the whole electronicthermostat

Besides the reached increment in technical capability we can say that we are nowmuch more aware of the importance

14. Lesson learned.

The lessons learned during the AE are related to both technical and managerial matter.Follows a list of the most important:• During the planning of the development of products using new technologies, it is

necessary to reserve sufficient men-hours for understanding implications aboutcomponent costs and supply and about their use. During the introduction of a newtechnique an expert in that field should guide the process.

• It is necessary to keep a tight control on the project management especially whensoftware development is a central issue. We underestimated this aspect during the firstwork-plan definition.

• It is very important to consider more alternatives from the beginning both in the designmethodology (micro selection) and in the fabrication choice.

• People involved in an ambitious project should work full time on it. This helps tospeed up the project and get people more committed to it.

• CAD systems require sufficient men hours to be used properly by engineers. So, whennew CAD system are requested in a project the training should be done before (orfrom) the beginning.

• The fuzzy logic is very efficient for implementing both the control model and thecalibration adjustments to fit with the real application.


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• The software engineering is fundamental for the cost definition. In fact a goodoptimisation of routines allow the use of cheaper microcontrollers.

• White good market is a very competitive one. Projects should be managed by having thecost as a fundamental boundary condition; design choices and circuit solutions has to bederived from these conditions (the choice to use shift registers obeys to this projectapproach).

• The fuzzy logic allow the electronic engineers to implement the know-how of thecompany into the control system without forcing the old experienced technicians to bedeeply involved into the project.

15. Resulting product or process, its industrialisation and internalreplication

The industrialisation of the FLTR has to be preceded by some preliminary steps:

• software full testing;• reliability testing of the full system (HW/SW) in terms of Failure mode and Effects

Analysis (FMEA);• certifications:

EMC and EMI certification (CE mark),IMQ-VDE – UL certification for safety.

The steps have been completed before the end of May 1998. They required many man-hours because of the software assessment in all real conditions and a long time for thecertifications.The certifications have been performed by ‘Prima srl’ for the EMC and EMI and ‘IMQ’(One of the most important Italian institute for quality assessment) for the safety.The industrialisation has been carried out in co-operation with the subcontractor forfabrication who made the prototypes with automatic production lines SMT. This selectionwas based on the fact that this subcontractor has an already defined production flow withspecial software for pick & place machines and customised temperature cycles for thesoldering ovens. As a consequence all the industrialisation phases were speeded up.Nevertheless, as already agreed with the subcontractor, at the end of the industrialisation,EGO will be the only owner of all the software for the machines set-up. Therefore, in caseof better offers from other board makers having compatible machines, the software could beforwarded to them. The EGO products are fully custom thus the industrialization phases typically involvesthe complete manufacturing of a dedicated assembly:• definition of the position of the human interface I/O devices (buttons, displays, LEDS,

…) with the customer,• PCB design as a consequence of the previous point;• adjustments in the software for machines set-up;• production start-up.

It should be noticed that at the end of 1Q 1999 all tests (functional, electrical, reliabilityand EMC) have been successfully concluded and the new electronic thermostat has beenincluded in the EGO products portfolio, and is now available to a wide range of customers


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About 34 kEUR more were spent for the industralisation phase (9 subcontracted). FirstSales are foreseen in 3Q1999

• Adjusting the firmware to the specific customer (10 person/days)• Further reliability check (25 person/days, 8 kEUR investments)• Electric and functional testing (10 person/days)• Preseries production (9 kEUR subcontracted)

The acquired technology will be exploited in the next future in different product updates ofthe EGO production line. Some examples are:

a) Thermostats for washing machines that will constitute replaced by electronic controlsystems for the same application: WMECS;

b) Thermostats for dishwasher that will constitute replaced by electronic control systemsfor the same application: DWECS;

c) Switches for ovens that will constitute replaced by function encoders with electronictimer: TIMERS;

d) Thermostats for ovens and hotplates that will constitute replaced by control systemlike the one designed in the AE: FLTR.

16. Improvements in the competitive position

The new technology and introduced features allow EGO to offer cost effective (25%cheaper than competitors at the best of our knowledge) customised components to thewhite good industry.The cooking equipment manufacturers who will choose EGO as their supplier will be ableto provide their final customers with appliances which can compete, thanks to a very goodcost performance ratio, with the most advanced solutions available on the market.With the introduction into the market of a fuzzy logic regulator, that is not yet used byovens producers, a market share increase of 10-15% in 2-3 years seems reasonable to bereached in the higher performance cooking equipment.Nevertheless, the improvement in the competitive position is more visible by analysingthe whole marketing strategy of the company.As already said in the chapter 6, two main considerations are important in order to betterexplain the EGO Italiana strategy into this market.1. The market opportunities are moving from the high end equipment toward the medium

performance applications.2. The concentration trend will impose new market penetration strategies in which the

technological innovation will play the dominant role.EGO Italiana, being market leader, is one of the candidates to win the concentration match.One of the most important condition (because of the first consideration) is to be successfulin the conversion to electronics.The business plan for the FLTR states that, in order to increase the quantity of soldthermostats, the electromechanical thermostat must be partially replaced by the new one.


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In the business plan the present product represents 43% of the total production ofthermostats made by EGO Italiana, which is the part used in ovens with electric cook-topsby our customers.It is assumed that the new FLTR will be sold in a configuration in which five standardelectromechanical thermostats are replaced by one electronic device. In case of otherconfigurations the economical considerations do not change.

The market evolution after the AE is:

Year Margin of Current

+New product sales [MEUR]

Margin with current

product only [MEUR]

Difference

[MEUR]

1999 0,638 0,53 0,1082000 0,952 0,51 0,442

2001 1,433 0,48 0,953

The profit margin for the current product and the FLTR are compared in thefollowing graph

0

0,2

0,4

0,6

0,8

1

1,2

1,4

1,6

1997 1998 1999 2000 2001

Margin with theCurrent Product only[MEUR]

Margin with both theNew and the CurrentProduct [MEUR]

The present product is a mature one, so selling price and unit margin are not expected tovary during the next years.The FLTR is introduced into the market at a price that will decrease with time because ofmarket competition; its unit margin is expected to increase anyway because of theefficiency improvement for both components acquisition and production productivity(both affected by scale factors).The turnover of the sold FLTR is foreseen to be equal to the number of the presently soldelectromechanical thermostats to 2000 year.The conversion to electronics of the other products in the EGO’s portfolio, in order toreach the goal of remaining a market leader in a more concentrated situation, imposes to addnew features to the existing products (as it happened with the product developed in theAE).

a) Thermostats for washing machines will be replaced by electronic control systems forthe same application: WMECS


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b) Thermostats for dishwasher will be replaced by electronic control systems for thesame application: DWECS

c) Switches for ovens will be replaced by function encoders with electronic timer:TIMERS

d) Thermostats for ovens and hotplates will be replaced by control system like the onedesigned in the AE: FLTR

It is possible to give marketing figures, in terms of pieces and turnover, by virtue of theview given by the main customers as Electrolux, Whirpool and Merloni. Generalagreements have been reached with them being E.G.O. market leader for electromechanicalproducts and so giving them enough guarantee for a positive conversion to electronics.The company turnover, split into the electronic business and the standardelectromechanical business has, as a consequence, the following trend:

The payback period can be easily determined on the basis of the table above.Considering a global investment for the industrialisation (including the FUSE budget) of 90KECU, the investment will be paid back in the year 1999. If this cannot be considered avery best performance, the real added value of the AE is to start with the electronics andthis goal is on the way to be reached.The total cumulated profit in three years life-time is estimated 1.5.MECU. Consideringthat the company expects to spend in the next two years further 100 kECU (certification,engineering of the new panel board, setting up mass production, advertisement, training ofsales forces, market analysis), the estimated Return of Investments (ROI) is still very highmore than 700%!

E.G.O. Italiana total turnover

0102030405060

1998 1999 2000 2001

Years

MECU

Tot. Electronics Tot. El. Mech. Total


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17. Added value to the portfolio and target audience

Summary of Best Practice

The peculiar best practice of this AE mainly concern the following points:

On the technical side:♦ The fuzzy approach for the control of the power sharing♦ The use of the Simulink tool and the Fuzzytech routines of the PIC

microcontroller

On the managerial side♦ The very tight control of the workplan♦ The resource allocation and the choice of the place where most of the work has

been carried out (At the subcontractor’s premises)

On the economic side♦ The internal replication (in the washing machine product line)♦ The outstanding value of the ROI

The target audience should be all the companies involved in the white goods fabrication andin all other industrial business fields.The dissemination should be done for the industries dealing with components for whitegoods starting from one year from now.The information that can be given during the dissemination are all the produced in thisdocument except the schematics, the control model and the software.We think in any case that we can persuade the companies of our industrial field (whitegood component suppliers) that the electronic technology innovation can be managed withthe proper support and management effort.We strongly believe that the diffusion of an electronic culture among our competitors will atthe end create new market opportunities for the company since also our possible customerswill become more aware of the new facilities that can introduced into their equipment thanksto the new available technology.The fact that EGO has started its way through the innovation path a year in advance andits firm commitment in proceeding along the same route by possibly introducing moreadvanced electronic features (like ASIC and microsensors) will assure the company to leadthe technology race in a mid-term range.Fuzzy temperature controllers might also be interesting in different industrial sectors somepossible examples are:

Ø The irrigation and water treatment (PRODCOM: 01, 29, 40) field where anenergy saving requirement is also present

Ø The plants growing and greenhouses field (PRODCOM: 01, 02) where thetemperature should be controlled according to very strict and different rules anda fast recovery from possible black-out is a must.


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Ø The fuzzy technology can be also effectively used for the food and beverage(PRODCOM: 15) industrial control where the actions should be decided on thebase of the measures of a lot of sensors.

In any case EGO agrees to participate in the future dissemination and training actions ofthe TTN for persuading other First users to use microelectronics and particularly the fuzzycontroller approach. As a prove of its very open dissemination attitude EGO has alreadyparticipated in three training and information events organised by the COREP TTN.

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