Portfolio of projects

1. Portfolio of projects Michael Hillman PhD, CEng FIMechE, MIPEM

2. Rolls Royce (Bristol) Aero Engines Undergraduate Apprenticeship Technology Engineer in the Installation Aerodynamics Department

3. Bath Institute of Medical Engineering ‘Working alongside those with healthcare problems and disabilities to develop and apply technology to improve the quality of life for all.’

4. Rehabilitation Robotics • Problem: Many people with severe physical disabilities can benefit from a “robot” to give them the ability to handle and manipulate everyday items. • The engineering challenge is how to integrate the technical device into the person’s environment • Solutions were developed through • User survey • Models / sketches / mock ups • Trials of prototype system with potential end users. • My contribution: Project management of team of industrial designer, mechanical engineer, electronics engineer, occupational therapist Design contribution • System design • Mechanical design • Software • Outcome – 3 working prototype systems • Workstation based • Mobile • Wheelchair mounted

5. 3D Ultrasound Breast Imaging Problem: Ultrasound scanning is regularly used for identification of breast tumours, but only gives a simple 2D image. A tumour is approximately spherical so it is easy to lose much of the 3 dimensional information in a simple 2D scan. Challenge: To design a scanner to collect and analyse a 3D dataset for better imaging and quantification of breast tumours. Working as part of a multidisciplinary team including medical physicists and a radiologist. My contribution: Heading the engineering aspects of the project, and all the mechanical design work. Involved in the user trials with patients coming through the breast clinic. Outcome: Working prototype system, but with much usability development still needed. A patent was granted, but lack of commercial drive from the team to push the exploitation of this patent.

6. Breast Elastography • Problem: How to identify potentially cancerous tissue without carrying out a biopsy • Background: Ultrasound elastography is an exciting technique in which the elastic properties of tissue may be quantified non invasively. A focussed ultrasound beam disturbs the tissue and an ultrasound imaging beam measures the amount of movement, so giving the elastic stiffness of the tissue • Working as part of a multidisciplinary team consisting of physicists and numerical analysis engineers from Bath and the Institute of Cancer Research. • My contribution: • Lead for BIME’s engineering contribution. • Design of electromechanical scanning tank for sample testing. • Design of ultrasound forcing transducer • Outcome from project: Working test rig handed over to team at the Institute of Cancer Research

7. Cardiac Phantom • Background: Software on nuclear medicine “cameras” calculates the ejection fraction of the heart (ratio of blood volume pumped to residual volume) • Problem: There is a need to produce a repeatable heart simulator (phantom) for quality control. Most phantoms are simple static simulators – this needs to be dynamic • Development process: Initial build of device didn’t work due to negative pressures causing ingress of air into the fluid actuation systems. • Solved by • Analysis of pressure drop through the system • Replacing valves and connectors with alternative components giving a lower pressure drop • Replacing simple sliding seal piston with rolling diaphragms. • Outcome. Prototype device built and working effectively. It requires more development to make it a reliable system.

8. Sip Cup Problem: People with dysphagia (for example because of motor neurone disease) require a restricted volume of fluid for safe swallowing Concept development: Several complicated solutions were identified involving a combination of valves, and tubes before the concept principles were put together to give a simple and effective solution Solution: A two part cup delivers a limited volume each time the cup is brought to the lips. Effectively the person is drinking a set volume from the bottom of the cup each time Prototyping and testing The first prototype used a vacuum formed inner cup within a standard mug. This wasn’t effective as the person drinking had to stretch their neck back to obtain a drink – solved by using an angled cup. Further prototypes used a combination of vacuum forms, vacuum castings and standard plastic caps. (At the time 3D printing technologies were not readily available) Outcome: The design has been developed for injection moulding.

9. Fold Flat Commode Chair Footrest concepts Inspiration • Project: To design a wheeled commode chair which will fold flat for use when travelling. • Protoypes • First prototype – investigated general configuration. • Final prototype – in use with volunteer clients. • Problems solved. Two problems were overcome by a combined single solution, that is an armrest brace which gave adequate strength and also acted as a catch to lock the seat back in its upright position. Several concepts were investigated for the footrests • Shown to several manufacturers but considered to be too expensive as an end product • Lessons learnt: • Careful use of 3D CAD allowed the development of a folding mechanism where the parts didn’t interfere with each other. • Even though a small detail, the position of the footrest was vital to the seating position of the user

10. Brittle Bone Potty Seat • Problem: Children with brittle bone disease need to be handled very carefully, for example when toileting. The potty seat needs to have several adjustable support surfaces to allow the parent to safely handle the child. • Background: Early work was carried out by several earlier engineers with a product design background. I was give the task of designing for small batch manufacture. • Manufacturing concepts used (some new to BIME) • Extensive use of laser cut aluminium parts. One bent component takes the place of several individual components satisfying differing functional requirements as well as locating the other components to facilitate welding. • Main cushions moulded from polyurethane • “Off the shelf parts” Obviously items such as castors, but also the potty is a “Wilco” dog bowl!

11. Omni Wheelchair • Problem: Wheelchairs are difficult to manoeuvre in a confined space – would this be helped by some form of omni-directionality? • Background: Many omni-directional mechanisms are both complex and expensive. BIME identified a simple robust approach • My contribution: To integrate the omni-directional function into a wheelchair base. • Suspension: I identified the need for suspension to keep all four wheels in contact with the ground. This comprises a rear subframe holding all the power components and at the front, a pivoting beam with a torsional rubber spring • User control was investigate using a virtual reality simulation. • User feedback: The design was reviewed by a wheelchair users focus group • Lessons learnt: • Requirements for outdoor use conflict with requirements for indoors manoeuvrability • Manoeuvrability is a compromise between Size of chair, Directional modes and an intuitive control system.

12. Cervical head brace • Problem: After accidents those with suspected neck injuries are put in a cervical collar. Existing collars are uncomfortable and do not provide fully effective immobilisation • Challenge: To develop a better head brace • Starting from earlier research work in Bath at RNHRD Hospital & BIME • Working collaboratively with the Helen Hamlyn Centre for Design. • IP for project is to be protected, so images are chosen to only give a partial view of the design process. • Measurement & Testing • Developed test methods for degree of immobilisation and interface pressures. • Immobilisation measured using XSens accelerometer sensors & CODA active IR markers. • Interface pressure measured using Tekscan pressure sensors • Led application to MHRA for Clinical Investigation • Main tests involved extraction of volunteers from a wrecked car. • Outcome: Work still in progress. Contacting potential manufactures for potential commercialisation.

13. Referral “one-offs” • Referral service: • BIME provides a service to the Royal United Hospital to produce one-off solutions primarily for the Children’s Centre and Medical Physics Department • Challenge: • Requires efficient solutions within a limited budget • Often working to tight timescales to meet patient’s needs. • Projects illustrated: (top left, clockwise) • Steps for child with restricted growth to reach sink. • Modified elbow crutch for patient with carpal tunnel syndrome – angled handle relieves pressure on the wrist. • Steps to enable child with restricted growth to climb off stair lift • Trolley to carry oxygen therapy equipment for child at school.