Initial ideation revolved around the mixed-reality continuum. Exploring the implementation of fiber actuators such as Nitinol Wire as introduced in 3.4.3, configurations of actuators could be arranged to realistically replicate the lifting motion of the pelvic floor muscles. For this, a wire core would run through a flexible tubing, protecting the soft elastomer that would be overmolded on top.

Acting as an elastic sling constrictor mechanism, the pelvic floor muscles sit ‘U’ shaped around the vaginal canal.

With a mechanical solution, wire driven by winches can be housed within tubing to protect from slicing.

Ultimately, due to its versatility and available facilities such as the vacuum former, silicone rubber was ultimately chosen to be used as the elastomeric material for tactile anatomical sections, particularly for its ability to be pigmented as desired, overmolded, and range of shore hardnesses.

Needing specific organic anatomical structures to be created in silicone, 3D printed molds were used to form the basis of anatomy re-creation. Modeling of anatomy and mold creation was conducted in SolidWorks.

Key features necessary for the design of effective molds included: locator pins, fill channel, and air escape holes. The flexibility of the silicone meant that the presence of mild undercuts were acceptable, enabling many more organic forms to be created without constraint.

Needing a method to test and evaluate the performance of the mechanical system, a rig was designed. To facilitate both vertical and lateral movement for anatomically accurate simulation of the PFM movement through contraction, rails were necessary to control the angle of test piece movement. Subsequently, to ensure retention following a full contraction sequence, an elastic resistance was added to encourage a natural position ‘at rest’. Ultimately, the mechanism would be driven by dual motors located at the base of the the rig, controlled by a micro-controller circuit.

These controls allow for flexibility and a range of pathology to be presented, conforming to functionality and performance specification requirements- specifically showcasing a range of muscular tone.

Assembling the circuit with the rig, control over degree of rotation was extremely difficult. The muscle piece could be wound, however the code relied on precise timings for minute gradations differentiating between different muscular tone presentations. The motors also struggled to wind the insert to the top of the rails against the elastic resistance of the band.

The clinical champion was presented with a working proof-of-concept for evaluation against haptic and functional realism. A low-fidelity simulated digital palpation scenario was enacted, from which feedback was provided.

The vaginal canal is not a circular structure, and therefore required a significant female mold piece to create the cavity. 2 stages of molds were designed for the piece.

Stage 1: 3-part mold with ridges to recreate vaginal ruggae, filled through the female mold to minimise air bubble formation in the 1.5mm thick vaginal wall mold cavity.

Stage 2: Open-faced mold for even part thickness, minimising tooling material. Female mold from stage 1 remains within the molded part cavity for structural rigidity, and slots into a hole within the stage 2 mold seamlessly.

Creation of a modular offering, as identified in competitor research, opens for versatility and adoption for future development. A larger context unit will house all active electrical components, enabling interchangeable modules to be placed seamlessly and safely- providing key anatomical landmarking, as well as crucially a tool to help establish empathy and situational simulation.

In this concept, gears would power the winch mechanism, lifting the muscle insert. Silicone anatomical elements were affixed through bungs pushed through a frame.

A remote controller was necessary to house all inputs for simulated functional components. This controller was designed for ease of comprehension, following real pelvic floor examination scripts and sequences for accurate simulation of procedural scenarios. To suit the flexibility of user’s teaching or leaning styles, the controller can be used as a docked panel or as a remote controller.

Controls needed to use clear language and existing medical semantic networks in labeling and semiotics to maximise learning outcomes in the experience design, providing clear feedback and matching the controller to real examinations.

As a comparatively small product housing electrical components, design for manufacture was essential for correct arrangement of components. Injection molded was chosen as the most appropriate manufacturing method for the volume and speed. Two most commonly used plastics are evaluated below for manufacturing suitabiltiy.

Components are assembled and held in place through compression. 4 screw holes hold the casing halves together, meeting at a PCB that acts as a structural shelf. Components are butted up to these elements, enabling a simple and cost-effective assembly, maintaining a sleek simplistic product.

The product will be used in mock examination scenarios, and therefore teaching will be conducted with the model placed upon a hospital bed. With presence of lubrication or gloved hands, there is a possibility of a hand-held controller being dropped. Therefore, drop tests were conducted to ensure this specification point was met.

Used to strengthen injection molded parts, ribs and gussets support elements within a part. Ribs are connections between elements such as screw holes and part walls, whereas gussets support free-standing elements.

Iterating the controller design following FEA analysis, these elements were added to the free-standing screw holes of the top and bottom casings, aiming to increase the product durability.

Determining the geometry and dimensions of all subsequent parts, the contextual body model was carved from orange foam, partitioning the module section once a rough form had been achieved.

To conform to the general body shape, the mannequin was portioned to be vacuum formed. Providing space to accommodate for the motor and gear, the module had a filled base within which structural elements such as pulleys and rails were embedded.

The vertical range of contractile moton was determined to reach a maximum of 7cm. Therefore, the full mechanical range of motion was created to be executed by a bobbin’s rotation, as controlled by a stepper motor.

Again utilising overmolding, the final silicone insert was cast in 2 stages. Requiring 8 parts, each mold stage required 4 parts, with the internal female mold remaining common across both processes as a structural and locator mechanism.

The anus was molded inversely, and was reversed upon demolding to create a realistic puckered effect. This insert incorporates external aesthetic and haptic elements, whilst incorporating a flange and locator holes for assembly with the module casing.

Subsequently, for creation of a working prototype, the controller was altered to incorporate electronic components available in a functional manner.

Due to limitations of time and resource, components remained wired to the base unit; ideally a wireless transceiver module such as the HC-12 would be used to control movements remotely.

The silicone piece here fitted within the module successfully molded with pigment, creating an effective aesthetic and haptic evocation of the relevant anatomy.

A user evaluation was conducted to assess the experiential functionality and success of the module piece against its specification points, as well as the usability of the proposal generally, specifically centered around the remote controller.

The paint for the mannequin was colour matched against the silicone insert. Due to the constraints of limited time, it was decided that for purposes of testing, separate models for a working concept and aesthetic concept would be delivered.

The larger context piece would, in production, be vaccuum formed around a substrate such as this, creating a large lightweight structurally rigid frame needing shelving and fixtures to house electronic components.