Periodic Report Summary - SSHOES (Special shoes movement)
The World Health Organisation (WHO) estimates that more than 334 million people will suffer from diabetes in 2030, as mentioned in 'www.who.int/diabetes'. In 2009 the amount of affected people was 220 million. The 'diabetic foot' is one of the most frequent outcomes of this disease.
The SSHOES project addressed the development and demonstration of new sustainable production capabilities for diabetic feet, providing high added value, consumer centred product concepts for footwear and insoles. More specifically, the project targeted design and definition of industrial paradigms and infrastructures related to the footwear industry, which is characterised by large numbers of traditional small and medium enterprises (SMEs) facing global competition. The aim was to capitalise on new competitive strategies based on demand product differentiation and customisation in order to deliver high quality products to individual consumers. Most of the results would also be directly applicable to the general footwear sector, such as occupational or fashion footwear.
The specific research and technological development (RTD) topics which were addressed by the project included:
1. integration of three-dimensional scanning, design and customisation tools. The latter was based on biomechanical and biomedical aspects, but considered style and aesthetics as well.
2. adaptive production processes and technologies that guaranteed functionality, quality, performance and healthcare.
3. devices with innovative sensing and actuating functionalities. The aims were improving comfort, controlling and modifying the product characteristics accordingly.
4. innovative high performance materials with self-adaptive properties to optimise fitting to the consumers' anatomy and biomechanics whilst guaranteeing comfort and aesthetic quality.
5. eco-sustainability of the product by using proper materials and production processes.
6. development of protocols, methods and technologies for functional assessment of products considering the environment of use and the individual consumer.
7. modelling the human behaviour, in particular the biomechanics of the lower limb.
A review of biomechanical variables and footwear features was completed and reported and different measurement approaches were evaluated. In addition, the algorithm that would relate the different input parameters, i.e. biomechanical variables, to design features was formulated. This algorithm should be an artificial neural network (ANN), more precisely a 'multi-layer feedforward neural network or multilayer perceptron (MLP)' that would be trained by feeding it with experimental data. The output would be footwear design features and specifications. Huge experimental data relating customised footwear features to biomechanical parameters were already collected and analysed in a pilot. Interesting new results came up. Some were directly applicable by the footwear manufacturers and designers. The main study was still ongoing and more and stronger results were expected.
For the subjects studied so far, varying the apex angle had a greater effect on peak pressure than changing the rocker angle. The same shoe was not minimising pressure for all subjects. This underpinned the importance of bespoke design.
Furthermore, criteria for comparing foot and last measures were defined. The software tools (Infohorma) for extracting those measures and performing the mentioned comparisons were programmed and deployed in an experimental study trying to establish fit allowances. A prototype was prepared and its use had started by the end of the reporting period.
For activity monitoring purposes several commercially available accelerometers were identified and tested. One of them would be used for the project. A protocol for monitoring gait activity was defined. It was possible to distinguish different activity levels from the accelerometer readings. The developed algorithms were tested and adjusted. The main study, aimed at obtaining 'usual gait activity levels' for the diabetic population, was carried out in parallel in Spain and United Kingdom.
Big advances were made in the development of computer aided design (CAD) tools:
1. software for last design based on morphometric tools which permitted to design a specific last for specific feet, according to biomechanic criteria coming from the Infohorma tool
2. a software tool for foot deformation based on morphometric tools and positioned in an homogenous way with the last
3. software for designing outsoles according to the parameters of interest coming from the ANN, as well as according to others more related to style and fashion was developed and deployed
4.a specific architecture was designed to integrate different CAD and computer aided manufacturing (CAM) elements through web services, setting up the basis for the scenarios to be implemented.
A fit simulator evaluating the interaction between upper shoe material and foot was also developed. This required characterising different leathers, doing mechanical tests and then virtually placing the feet into a shoe made of those leathers previously characterised. The appearing forces were then estimated using a finite elements method (FEM). An additional simulator for insole and outsole materials, based on the experimental work done on current materials in use, was ready to be integrated with the specific architecture.
Insole and outsole materials were mechanically characterised. FEM was used to model and predict their single and combined behaviour. Ultra high speed milling of soft materials was improved. Sustainable polyurethane (PU) formulations with high shape retention were produced in two densities and three more densities were planned to follow. Moreover, the architecture for integrating the different project results and data was defined. By the end of the reporting period the system needed to be fed with data.
A prototype capable of measuring pressure at four points as well as humidity and temperature inside the shoe was developed. A prototype for monitoring plantar pressures over a period of approximately seven days was also developed, as well as a novel position sensor based on the Hall effect, allowing to evaluate foot motion inside the shoe.
In terms of the three-dimensional foot scanner, a version with eight cameras was developed. The new scanner had a higher resolution and a bigger scanning volume. Using eight cameras instead of four also improved precision, mainly at vertical surfaces in the frontal plane. Additionally, plantar pressures of one foot were registered during the three-dimensional scan of the other one. A software tool matching plantar pressures with the virtual foot volume was developed, as well as an accessory for raising the heel during the scan, which was designed, constructed and deployed during this reporting period.
On the other hand, a prototype of the minilab was developed. The minilab should be an easy to use measuring system delivering parameters related to the customer's gait mechanics. The system consisted of four synchronised cameras with their corresponding lighting and a forceplate. A biomechanical model of the foot and ankle was defined. The outputs were foot and ankle motion, three-dimensional for the ankle and forefoot to rearfoot and two-dimensional for the first toe to forefoot, ground reaction forces and moments around the three defined joints. The user interface was being improved by the end of the reporting period.
Two different industrial robots were used to allow for a flexible production environment. New steering software was programmed and hardware accessories, such as a spindle, a tool changer and a material feeder were designed. In addition to the technologies that were developed, two main scientific results and one patent were achieved in the reporting period, namely an application for a Spanish patent on the magnetic positioning sensor and an application for a European extension of the above referred patent.
The project resulted in two doctoral theses. The first one was entitled 'Modelo geométrico biodeformable del pie. Aplicaciones a la fabricación de calzado personalizado', by Miguel Davia from the Footwear Technological Institute (INESCOP), which was planned to be defended before June 2011. The second was entitled 'Multidisciplinary techniques for the simulation of the contact between the foot and the shoe upper in gait. Virtual reality, computational biomechanics and artificial neural Networks', by Maria José Rupérez from the Department of Mechanic and Materials Engineering at the Universitat Politecnica de Valencia (UPV), which was to be defended on 9 June 2011. Information on the project was provided at 'www.sshoes.eu'.
The SSHOES project addressed the development and demonstration of new sustainable production capabilities for diabetic feet, providing high added value, consumer centred product concepts for footwear and insoles. More specifically, the project targeted design and definition of industrial paradigms and infrastructures related to the footwear industry, which is characterised by large numbers of traditional small and medium enterprises (SMEs) facing global competition. The aim was to capitalise on new competitive strategies based on demand product differentiation and customisation in order to deliver high quality products to individual consumers. Most of the results would also be directly applicable to the general footwear sector, such as occupational or fashion footwear.
The specific research and technological development (RTD) topics which were addressed by the project included:
1. integration of three-dimensional scanning, design and customisation tools. The latter was based on biomechanical and biomedical aspects, but considered style and aesthetics as well.
2. adaptive production processes and technologies that guaranteed functionality, quality, performance and healthcare.
3. devices with innovative sensing and actuating functionalities. The aims were improving comfort, controlling and modifying the product characteristics accordingly.
4. innovative high performance materials with self-adaptive properties to optimise fitting to the consumers' anatomy and biomechanics whilst guaranteeing comfort and aesthetic quality.
5. eco-sustainability of the product by using proper materials and production processes.
6. development of protocols, methods and technologies for functional assessment of products considering the environment of use and the individual consumer.
7. modelling the human behaviour, in particular the biomechanics of the lower limb.
A review of biomechanical variables and footwear features was completed and reported and different measurement approaches were evaluated. In addition, the algorithm that would relate the different input parameters, i.e. biomechanical variables, to design features was formulated. This algorithm should be an artificial neural network (ANN), more precisely a 'multi-layer feedforward neural network or multilayer perceptron (MLP)' that would be trained by feeding it with experimental data. The output would be footwear design features and specifications. Huge experimental data relating customised footwear features to biomechanical parameters were already collected and analysed in a pilot. Interesting new results came up. Some were directly applicable by the footwear manufacturers and designers. The main study was still ongoing and more and stronger results were expected.
For the subjects studied so far, varying the apex angle had a greater effect on peak pressure than changing the rocker angle. The same shoe was not minimising pressure for all subjects. This underpinned the importance of bespoke design.
Furthermore, criteria for comparing foot and last measures were defined. The software tools (Infohorma) for extracting those measures and performing the mentioned comparisons were programmed and deployed in an experimental study trying to establish fit allowances. A prototype was prepared and its use had started by the end of the reporting period.
For activity monitoring purposes several commercially available accelerometers were identified and tested. One of them would be used for the project. A protocol for monitoring gait activity was defined. It was possible to distinguish different activity levels from the accelerometer readings. The developed algorithms were tested and adjusted. The main study, aimed at obtaining 'usual gait activity levels' for the diabetic population, was carried out in parallel in Spain and United Kingdom.
Big advances were made in the development of computer aided design (CAD) tools:
1. software for last design based on morphometric tools which permitted to design a specific last for specific feet, according to biomechanic criteria coming from the Infohorma tool
2. a software tool for foot deformation based on morphometric tools and positioned in an homogenous way with the last
3. software for designing outsoles according to the parameters of interest coming from the ANN, as well as according to others more related to style and fashion was developed and deployed
4.a specific architecture was designed to integrate different CAD and computer aided manufacturing (CAM) elements through web services, setting up the basis for the scenarios to be implemented.
A fit simulator evaluating the interaction between upper shoe material and foot was also developed. This required characterising different leathers, doing mechanical tests and then virtually placing the feet into a shoe made of those leathers previously characterised. The appearing forces were then estimated using a finite elements method (FEM). An additional simulator for insole and outsole materials, based on the experimental work done on current materials in use, was ready to be integrated with the specific architecture.
Insole and outsole materials were mechanically characterised. FEM was used to model and predict their single and combined behaviour. Ultra high speed milling of soft materials was improved. Sustainable polyurethane (PU) formulations with high shape retention were produced in two densities and three more densities were planned to follow. Moreover, the architecture for integrating the different project results and data was defined. By the end of the reporting period the system needed to be fed with data.
A prototype capable of measuring pressure at four points as well as humidity and temperature inside the shoe was developed. A prototype for monitoring plantar pressures over a period of approximately seven days was also developed, as well as a novel position sensor based on the Hall effect, allowing to evaluate foot motion inside the shoe.
In terms of the three-dimensional foot scanner, a version with eight cameras was developed. The new scanner had a higher resolution and a bigger scanning volume. Using eight cameras instead of four also improved precision, mainly at vertical surfaces in the frontal plane. Additionally, plantar pressures of one foot were registered during the three-dimensional scan of the other one. A software tool matching plantar pressures with the virtual foot volume was developed, as well as an accessory for raising the heel during the scan, which was designed, constructed and deployed during this reporting period.
On the other hand, a prototype of the minilab was developed. The minilab should be an easy to use measuring system delivering parameters related to the customer's gait mechanics. The system consisted of four synchronised cameras with their corresponding lighting and a forceplate. A biomechanical model of the foot and ankle was defined. The outputs were foot and ankle motion, three-dimensional for the ankle and forefoot to rearfoot and two-dimensional for the first toe to forefoot, ground reaction forces and moments around the three defined joints. The user interface was being improved by the end of the reporting period.
Two different industrial robots were used to allow for a flexible production environment. New steering software was programmed and hardware accessories, such as a spindle, a tool changer and a material feeder were designed. In addition to the technologies that were developed, two main scientific results and one patent were achieved in the reporting period, namely an application for a Spanish patent on the magnetic positioning sensor and an application for a European extension of the above referred patent.
The project resulted in two doctoral theses. The first one was entitled 'Modelo geométrico biodeformable del pie. Aplicaciones a la fabricación de calzado personalizado', by Miguel Davia from the Footwear Technological Institute (INESCOP), which was planned to be defended before June 2011. The second was entitled 'Multidisciplinary techniques for the simulation of the contact between the foot and the shoe upper in gait. Virtual reality, computational biomechanics and artificial neural Networks', by Maria José Rupérez from the Department of Mechanic and Materials Engineering at the Universitat Politecnica de Valencia (UPV), which was to be defended on 9 June 2011. Information on the project was provided at 'www.sshoes.eu'.