4.1. Restrictions and Brief
This subsection provides an overview of the constraints and details the brief development of the toy. This toy specifically focuses on blind and visually impaired children and aims to stimulate and accelerate the acquisition of motor skills within this group.
Evyapan [
6] suggests that familiar surroundings can promote exploration. Hence, the product must encourage safe exploration and stimulate children’s curiosity and desire to explore, stimulating movement.
Due to the developmental differences among blind and visually impaired children, defining a specific age range for the toy is challenging. Typically, sighted babies learn to walk between birth and three years old [
25], but blind children often experience developmental delays [
5]. Therefore, the toy will be intended for children up to five years old and will consider the anthropometric measurements of children in this age range.
The toy’s design must consider the diverse needs of the target audience, including sensory stimulation beyond vision [
6]. Thus, the toy should be designed to appeal to both touch and smell [
2], which can be achieved through both material selection and the design itself.
A set of restrictions was established for the final product. As a children’s toy, the materials must be non-toxic and safe to handle [
24]. Moreover, the toy’s components must be lightweight and properly dimensioned, avoiding sharp edges to ensure safe play.
As mentioned, the toy should be designed to create a safe exploration space that enhances children’s receptiveness to learning. Naturally, this highlights the necessity of defining a playing area. An activity mat easily establishes an area once it can delimitate the space. Considering the typically large dimensions of such products, the mat should be divisible into parts for easy transport and storage. A mat can also help the child identify the play area, possibly through the toy’s texture. Moreover, it must provide comfort for sitting and playing. Considering all these factors, along with the considerations mentioned in the previous paragraph, cork was chosen as the main material for the toy.
Research indicates that parents often use sound, such as noisy toys or their voice, to motivate children to move by following the noise [
26]. In line with this, the toy should be designed to offer similar stimulation. However, the sound source must be mobile to incite children to follow and move. Thus, noisy balls, which move easily and are easy for children to handle, were incorporated into the design. These balls, besides being auditorily stimulating, must also be tactilely intriguing, with varied textures for finger exploration. This design choice aims to facilitate movement and stimulate the children’s desire to follow the sound.
Allowing the balls to move freely was considered too unpredictable and potentially stressful for children, particularly given the potential for them to search everywhere with no specific indication. Simultaneously, the toy needed to be challenging to maintain children’s interest. This led to the idea of a circuit with a buildable ramp. Children are invited to construct blocks to create a path for the balls to roll down, then collect the balls to restart the game. This adds challenge, purpose, and repetition to the product, essential elements to maintain interest and facilitate learning. In this circuit, the repetition, building, and finding aspects provide essential learning opportunities, autonomy, and challenge.
In conclusion, the project brief defines a toy set primarily crafted from cork. It may include a divisible activity mat, a ramp that breaks into buildable blocks, and sensory balls that emit sound. The main objective of this toy’s design is to nurture the early development of motor skills in children, leading to greater independence. By creating a safe and stimulating environment, this product will meet the distinctive needs of blind and visually impaired children, making playtime both an enjoyable and enriching experience.
4.2. Development and Testing
This subchapter delves into the conceptual development process of ‘bumpi’. It begins with an overview of the initial sketches, illustrating how the concept of the toy first came about. This is followed by a discussion on the selection of the final idea. Subsequently, the development of the chosen concept will be detailed, including the tests conducted and the insights obtained along the way. The subchapter concludes with a presentation of the proposed design, preceding the creation of the full-scale prototype.
The development process started with an analysis of existing market products. Given the absence of any object specifically designed for the identified problem, the focus shifted to products with similar typology, function, methodology, or other characteristics that piqued interest. These solutions were also examined from a design perspective to comprehend their dimensions, proportions, and shapes.
The research revealed thicker activity mats typically divided into interlocking pieces, with a puzzle-like system being the norm. Consequently, this project adopted a similar approach, resulting in a mat divided into puzzle-like pieces.
Following this, freehand drawing exploration of shapes was conducted to generate a range of possibilities that could ultimately lead to a general proposal. This exploration, illustrated in
Figure 1, played a crucial role in solidifying the brief mentioned earlier. Please note that some of the textual annotations in the sketches presented in this subchapter may be in Portuguese.
Once the brief was well-defined, targeted and objective drawing exploration was carried out. The aim was to address specific challenges associated with the most promising ideas. This phase was a quest for solutions, focusing on the cart’s shape and operational methodology, the overall design of the ramp, and the strategy for assembling the blocks that would form it and its shape.
First, focus was particularly drawn to the design of the ramp.
Figure 2 below presents the outcome of this specific drawing investigation, which was conducted to determine the ramp’s composition and assembly method. The investigation was driven by the initial concept of creating a circuit with a building ramp, adding an element of challenge and purpose to the toy.
This sketch exploration suggested arranging the blocks in lines. This arrangement not only simplifies the shape of the blocks but also makes it easier for a child to assemble. This line arrangement creates several height levels, which were intentionally incorporated into the design. This feature increases the product’s interest by enhancing the sound the balls produce as they move and jump between levels. This variation in sound breaks the monotony of the noise emitted. This auditory difference is predicted to keep children more engaged during the balls’ fall, thereby increasing their interest and curiosity.
In addition to this, different fittings were initially conceptualized in these sketches. Some of these options were examined and tested using Fused Deposition Modeling (FDM) 3D printed models at a scale of 1:2. The resulting printed pieces are shown in
Figure 3 and
Figure 4, the latter presenting more details of the fittings. These practical tests enabled the selection of the most suitable fitting method, taking into account the type of cork to be used in the final product. Consequently, the shape incorporating V-cuts in the pieces was chosen as the optimal solution. This design simplifies the manufacturing process and ensures an easy fit, making the toy more straightforward and more accessible for visually impaired children.
In parallel with other development activities, an investigation was conducted to establish the dimensions of the toy components. This involved an analysis of the anthropometric tables found in Alvin Tilley’s book ‘The Measures of Man and Woman’. These tables provide data on human body dimensions across various developmental stages. Specifically, there was a focus on relevant data regarding the target group—children up to 5 years of age. This allowed to estimate the space required for the toy’s intended use and define the part’s general dimensions.
The ramp was divided into blocks, each line having a final inclined piece. A different final piece at the bottom of the ramp was also included in the set. This piece, designed as an open block, functions as a box to catch the balls at the end of the ramp. This box ensures that the balls stop moving, effectively completing the descent. The child can then easily retrieve the balls and restart the circuit.
The dimensions of these blocks were carefully determined to ensure they would be suitable for children. The width of the blocks was set at 50 mm, a size chosen based on an analysis of the dimensions of children’s hands, ensuring a firm grip. Two lengths were selected for the blocks: 75 mm for the smaller blocks and 150 mm for the inclined blocks and the box. The larger length of the inclined blocks results in a more moderate incline. This process resulted in a balanced and proportional division of the ramp. The total number of blocks required was determined by the ramp’s area and the blocks’ dimensions.
Figure 5 provides the detailed measurements of the pieces.
After defining these specific measurements, the general dimensions of the mat were determined. An analysis of available mats on the market was conducted. However, given the space required for the child to complete the designed circuit, it became apparent that the mat designed would need to be larger than most. Thus, a larger, square mat of 1500 mm × 1500 mm satisfies this need.
Next, the division of the mat into pieces was explored. Initially, a division into four parts was considered (
Figure 6), and full-size mockups were made for testing (
Figure 7). These models revealed that the size of a single piece was excessive, making it more difficult to handle. Therefore, approaches with more pieces were explored, analyzing compositions with nine and 16 pieces in SolidWorks 2022 (Dassault systèmes, Paris, France), a 3D modeling program (
Figure 8). The option of nine parts was selected as the optimal choice, as 16 pieces were considered to be too many.
The nine pieces were designed intelligently and simply. They present a modular design, consisting of three models—the corner pieces, the intermediate line pieces, and the central piece. Therefore, there are four corner pieces, four intermediate pieces, and one central piece. The corner pieces interlock with the intermediate pieces and vice versa, and the unique central piece is located in the center, representing a logical assembly. The similarity of the shapes of the pieces also offers productive advantages, facilitating manufacturing processes and reducing time.
Finally, the proposal for the mat was obtained by adding the grooves needed for assembling the ramp and for the cart’s path. For this latest mat design proposal, presented in
Figure 9 below, the hole for the ramp was made with a cut similar to the design of the blocks. The cart’s path had already been explored in the initial designs, which presented some curves. However, it was simplified to ensure good functionality.
To emphasize the sound created in the circuit, additional oscillations in the balls’ path were considered. This was achieved by implementing dowels in the inclined pieces. The drawings in
Figure 3, which were previously presented, already show an attempt to identify the most strategic positioning options. A test was conducted using FDM 3D printing technology to print a set of pieces at a scale of 1:2 (
Figure 10). Two smaller blocks, one inclined block, and a ball were printed. In addition, other inclined parts with different dowel configurations were also printed with the same scale to evaluate the performance of each one. The tests were performed while the bottom blocks’ line was assembled, and the top piece was changed. The ball was dropped from the beginning (the higher point) of the top piece and its descent movement was analyzed. These tests were recorded to enable reanalysis and better comparison of the ball’s performance. It was concluded that the best arrangement for the dowels would be a vertical positioning in two lines. This conclusion was facilitated by the small-scale models, which provided tangible results, allowing for real-time testing of the ball’s behavior. Therefore, they were crucial in the decision-making process.
After selecting the best proposal, the inclined blocks incorporating the dowels were manufactured in cork at full scale (
Figure 11). The manufacturing process will be detailed in the upcoming subchapter intended for prototyping. However, it is important to note that strategically, the dowels were not glued to the cork, making it possible to remove them and also test the performance of the smooth surface of the pieces if needed. In addition to these parts, the smaller blocks were also produced. Having all the ramp’s components allowed for the conducting of assembly tests. Performance tests were also conducted using sensory balls previously purchased from the market. The full-scale prototype allowed us to test both the blocks’ V-fit and the dowels’ functionality. These tests were also recorded for later analysis, providing an opportunity to review the performance from a detached perspective, separate from direct involvement in the testing process.
As with the previous analysis of the small-scale 3D printed model, the full-scale fitting tests were successful. This larger prototype confirmed that the fitting methodology is functional and easy to assemble. Thus, it was proposed as the solution for the product.
The performance tests (
Figure 12) demonstrated that the movement of the balls was unpredictable due to their irregular surface. When the balls were dropped, their performance varied most of the time, often deviating from the path and falling off the ramp to the ground. Although oscillations in the sound were noticeable due to the application of this strategy, the balls landed unpredictably, failing to complete the circuit, and the purpose of the ramp was not achieved.
To address this result, experimental modifications were made by removing a portion of dowels and changing their configurations. The aim was to analyze if these changes would improve the balls’ behavior, particularly if they stopped falling and completed the path. However, these modifications did not achieve the desired results as the balls continued falling and exhibiting unpredictable movements.
Since the dowels did not perform as expected, they were manually removed from the pieces. Subsequently, more tests were performed on smoother surfaces (
Figure 13). It was found that the simple design option produced more sound than initially predicted, and the height difference between levels effectively momentarily enhanced the volume of the sound. Moreover, the balls rolled perfectly and reached the bottom of the ramp without constraints.
Upon analyzing these conclusions, it was decided to not implement the proposal with dowels. However, the design process needs to describe the tests conducted and report the insights gained, as these conclusions provided valuable knowledge and contributed to the continuous improvement of the toy in development.
The cart, another integral part of the toy, underwent similar developmental milestones. Including a cart in the toy was intended to enable the child to transport the balls from the end of the ramp back to the start. Given that children are still developing their spatial perception and orientation skills during the initial uses of the toy, it is predicted that they might find it challenging to discern the correct direction to the beginning of the ramp. This could frustrate children and discourage them from playing. Therefore, adding a defined path for the cart to follow was proposed, guiding the child and reducing potential stress.
The design process for the cart began with sketches of various shapes and compositions, initially considering multi-component structures but ultimately evolving into a single-piece design (
Figure 14). A full-scale model, created using FDM 3D printing and presented in
Figure 15, was used to analyze the interaction of small components that could integrate the cart. Although a multi-component cart could allow for rotating wheels, it was considered too complex for production in agglomerated cork material and potentially challenging for a child to handle. Consequently, a one-piece design was chosen for the cart because it might be safer for the child, given that it does not have small parts, and it is easier to produce as it requires fewer production processes and eliminates the need for assembly.
A cylinder was added to the bottom of the cart to further assist in directing the movement. This cylinder fits into a groove on the mat, guiding and helping the cart move along the predefined path.
The proposal for the cart’s design is presented in
Figure 16. Notably, the cart features a V cut on its sides, a design element transposed from the blocks that compose the ramp. This transposition of shape from one component to another helps further integrate the cart into the set and enhances the toy’s overall coherence.
Finally, attention was turned to the design of the sensory balls. Initially, designing the balls was perceived as a potential production constraint due to the different production processes required compared to the other components. Utilizing existing sensory balls already on the market was considered to overcome this. However, a market investigation revealed that due to their measurements, none of the options found were compatible with the designed circuit. Despite these findings, a set of balls, specifically the Infantino Textured Multi-Ball Set (Infantino, Diego, CA, USA), was acquired for testing with the prototype ramp to gather concrete data. This set is composed of six balls made of soft plastic material, all with different colors, textures, and dimensions: one white ball had a grooved pattern and a diameter of 5.8 mm; one yellow ball had four protrusions and a diameter of 5 mm plus protrusions 1.8 mm long; one 6.3 mm diameter coral ball was covered in small raised nodules; one purple ball had multiple circular indentations and a diameter of 6.5 mm; one 8 mm diameter green ball had horizontal ridges across its surface; and one blue ball was covered in small raised spheres with a diameter of 8.3 mm. However, as anticipated, the balls proved to be too large. Consequently, it was decided to design a proposal for the set of balls.
The exploration was guided by insights from the previous market analysis, particularly regarding the types and patterns of textures found on the surfaces of sensory balls. Various options were explored using SolidWorks (Dassault systèmes, France), a 3D modeling software. The balls were specifically designed in two halves, allowing for the insertion of different small objects to produce various sounds.
An initial test was conducted using FDM 3D printing technology to evaluate the textures of nine options. A group of volunteer reviewers, with their eyes closed, touched each half of the balls for the first time and provided feedback on the sensations they experienced and their preferences on texture. Based on this feedback, the top six textures were selected for the final design proposal (
Figure 17).
Subsequently, the FDM 3D printing process was again employed, with the specific purpose of fabricating both halves of each ball. Small objects such as a rattle, nuts, rice, and others were placed inside, and the halves were glued together (
Figure 18). Following this, a second round of tests was conducted. These tests reanalyzed the textures—this time of the complete balls—and also evaluated the performance of the balls rolling down the ramp and the sound they emitted. The tests were recorded for a more detailed post-analysis. The results were encouraging, with the balls working as intended. Consequently, this solution was implemented.
The development described culminated in a product proposal that aligns with the outlined brief (
Figure 19). The proposed product consists of a mat divided into nine pieces that assemble in a puzzle-fit system. In addition to the mat, the product includes a ramp composed of blocks. The blocks are designed to fit into the mat and are assembled in a specific order, both horizontally and vertically. Each horizontal line of blocks ends with an inclined piece, creating a multi-level ramp. Additionally, there is a cart that follows a predefined path from the beginning to the end of the ramp and the inverse on the mat, and sensory balls that produce sound when moved. This set represents a circuit that a child can play with repeatedly.
The proposal was materialized through the production of prototypes. Those prototypes will be presented in the next subchapter, along with the design adjustments that resulted from their testing.
4.3. Prototyping and Adjustments
To evaluate the concept of the developed toy, two full-scale prototypes were created. These prototypes were manufactured at the Camila Móveis factory, located in Rebordosa, Porto, Portugal. The aim was to test different components of the toy, with a focus on verifying the entire system and circuit. Furthermore, the aim was also to evaluate the fittings and monitor the toy’s performance throughout the entire play process.
In this subchapter, the production process of these prototypes is explained. This crucial phase of the project involved various manufacturing techniques and machinery. Each process step, from the initial cutting of the cork blocks to the final assembly, is detailed below. It is important to note that this was not a linear process. The results from each production test were analyzed and used to refine the process, leading to modifications and improvements. This iterative process ultimately led to the successful creation of effective and functional prototypes.
4.3.1. Initial Prototype
The production of the prototype began with the fabrication of the cork blocks. Smaller blocks were cut from a large agglomerated cork block using a sliding table saw. These blocks were cut with the specific height and width dimensions to fit the toy’s requirements. However, the length was kept intentionally longer than required. This was done to facilitate making the V-cuts, which would be easier to execute on longer blocks. Once the V-cuts were made, the blocks would be cut to their final, shorter length.
Once cut, these elongated blocks were planed using a SCM planer machine. This machine, manufactured by SCM Group (Rimini, Italy), ensured that the blocks were level and met the precise measurements required. The blocks were then returned to the sliding table saw for further adjustments. The saw’s height and angle were modified, setting the saw at 30 degrees to make the lower V-cuts on the blocks (
Figure 20). The saw’s height was adjusted again to make the uppercuts. However, this method was not applicable for larger blocks requiring a specific inclination, as it did not accommodate this requirement.
An alternative method was explored as a variation from the initial process. This involved machining other cork blocks on a HOMAG CNC machine (HOMAG Group AG, Schopfloch, Germany). The experiment had two objectives. First, it aimed to evaluate the practicality of using the CNC machine to produce these pieces. Second, it intended to compare this method with the initial process to determine which was more suitable.
More cork parallelepiped blocks were cut for this experiment using a sliding table saw. Subsequently, these blocks were prepared for machining on the CNC machine. An auxiliary wooden board was used to secure the blocks, which were attached using screws. Once the blocks were firmly secured to the board, they were affixed to the CNC machine, and the cork blocks were then machined (
Figure 21).
The machining process began with a drill shaping down the block, creating one side of the upper V-cut. This particular cut could not have been made by the saw. After this initial cut, the saw made the remaining three cuts—one upper cut and two lower cuts. This process ensured that each block was precisely shaped to meet the toy’s requirements. Subsequently, both the blocks produced on the sliding table saw and those produced on the CNC were cut to length, resulting in small blocks with a length of 75 mm (
Figure 22).
The production process for the larger, inclined blocks followed the same steps as those for the shorter ones until the point of completing the lower V-cuts. From this stage onwards, a different approach was necessary. To facilitate the creation of the upper V-cuts, the specific mold shown in
Figure 23 was designed and implemented. This mold facilitated the manufacturing of the pieces with inclination on the sliding table saw, similar to the first process used for the shorter pieces. The first step in creating this mold was drawing a guide line on an MDF board, representing the blocks’ desired inclination. An auxiliary block was then screwed to the board along this guide line. The position and angle of the auxiliary block on the board mirrored the intended shape and inclination of the larger blocks. This setup served as a mold and could be used to accurately shape the larger blocks, ensuring the V-cuts along the inclination.
Next, keeping the saw’s inclination at 30 degrees, the upper V-cuts were made on the inclined blocks on the sliding table saw (
Figure 24). In the end, the expected result was obtained.
This initial production phase was carried out to allow for dowel tests on the inclined blocks, as detailed in the preceding subchapter. Consequently, the fabricated inclined blocks underwent additional procedures. Once the general form was shaped using the sliding table saw, the blocks were transferred to another machine. On the multi-drill machine (Vitap, Poggibonsi, Italy), the drills were calibrated to achieve the desired hole spacing, and the holes were subsequently drilled.
Following this, all the short and large blocks underwent a manual sanding process. In the final step, the dowels were manually inserted into the holes in the inclined pieces (
Figure 11).
Since these pieces were initially produced to test both the fit of the blocks and the performance of the dowels, it was decided to produce only the necessary pieces. Thus, three additional pieces were produced to mimic the base for the ramp. These pieces consisted of three blocks, each measuring 150 mm in length, the same as the inclined blocks. Each piece featured an upper V-cut and a straight base designed to provide stable support for the entire structure.
As previously mentioned, the dowels did not perform as expected, leading to their removal. Interestingly, despite not being glued and just inserted into the cork holes for easy manual removal, most dowels proved challenging to extract. This difficulty occurred because the cork contracted when drilled and returned to its original position over time, tightening the holes and complicating the dowel’s manual removal.
Despite these challenges, this initial prototype performed well and led to good conclusions and improvements in the design. In addition, it was conducted to produce the remaining pieces, a crucial step in validating the entire proposal.
The production process then shifted its focus to the cart component. Mirroring the process used for the building blocks, a block of agglomerated cork was cut to the required dimensions. This block was then machined on the CNC machine. Due to the cart’s design as a single piece, several CNC programs were developed because multiple machining operations were needed—one for each face of the cork block. Once the programs were finished, the machining process began. It started with the bottom face of the cart, i.e., manufacturing the guide cylinders. The subsequent CNC program (woodwoot 7.2) crafted the side of the cart, outlining the shape of the wheels, and the front side. This same program was applied on the other side of the block. Finally, the last program allowed to define the thickness of the cart’s walls, opening the space where the balls would be placed.
Once again, an auxiliary MDF board was employed to secure the piece during machining. This process is carried out when the pieces to be produced do not have sufficient dimensions to be directly applied to the suction cups of the machine. As a result, an appropriate fixation would not be applied, and the piece would not be secure for machining. The cork block was screwed to the wooden board and machining was carried out. Whenever one CNC program was completed, the wooden board was removed from the machine, and the block was unscrewed. It was then rotated and screwed again for new machining on a different face. This resulted in small holes on the sides of the piece.
Figure 25 below provides a visual representation of this process. Captured in one of the moments after the block’s rotation, the image shows the cart attached to the wooden board, which was secured to the CNC machine.
Following the construction of the cart, its functionality was tested. A section of the track was crafted onto a small wooden board using CNC machining. The aim was to evaluate the efficacy of the movement strategy—the incorporation of cylinders at the base of the cart designed to guide the cart along the intended path. A curve segment was chosen for this evaluation as it represents a change in direction, providing an in-depth understanding of the cart’s performance. To provide a clear understanding of the test, the cart’s movement along the entire path segment was recorded. A single frame was extracted from this recording and presented in
Figure 26. This image visually represents the test, providing insight into the process.
Positive results were obtained from the test, confirming the effectiveness of the methodology applied. With no further improvements or adjustments required, the cart was finished. Manual sanding was performed, and a filling material was applied to the screw holes to make them less noticeable.
The next step was the production of the mat. Initially, the mat was intended to be manufactured from 20 mm thick cork. However, the unavailability of agglomerated cork of this size for prototyping led to a different solution—the sandwich method. This method involved using poplar wood and covering it on both sides with a cork sheet. Nine pieces of this wood were cut on the Biesse Selco SK4 automatic panel saw, which is a machine manufactured by Biesse S.P.A., Ginestreto, Italy. The cork sheet, on the other hand, was manually cut.
With all the parts prepared, the gluing process began. SOUDAL 170TX contact glue (Souldal Group, Turnhout, Belgium) was applied to one side of the cork sheet and the wooden board. After allowing a brief period for the glue to set, the cork sheets were affixed to both sides of the wooden board. This process resulted in wooden pieces that were sandwiched between sheets of cork. The pieces were then left to dry completely, solidifying the bond.
Figure 27 below provides a detailed view of the results of applying this process.
In parallel, another test was conducted to verify the functionality and sizing of the designed fitting for attaching the blocks to the mat. A small wooden board was used for this purpose, which was machined on the CNC after preparing the specific program. The machine drilled a hole in the wood, replicating the V-shape at the bottom of the blocks. Once the machining was complete (
Figure 28a), one of the blocks was fitted into the cavity, confirming that it was well-dimensioned and functional (
Figure 28b).
Subsequently, the CNC programs for producing each piece of the mat were developed while the glue was still drying. A program was developed for each piece of the mat to cut their silhouettes and hollow out the existing grooves. Once the sandwich pieces were dry, they were positioned on the CNC machine for processing these programs. The final step involved sanding the pieces both manually and with a handheld electric sanding machine (Shimano, Sakai, Japan) (
Figure 29) before they were considered finished.
In the final stage, all the pieces were assembled. The assembly process was smooth and efficient, confirming the ease of construction. All fittings were functional, performing exactly as intended.
At this point, only the balls purchased from the market were available. Although these balls were too large for the track that had been designed, usability and performance tests were conducted. It was considered that this size constraint did not interfere with the circuit very profoundly. It only affected the performance of the cart and the box at the end of the ramp, as the balls did not fit inside them. This would lead to a disruption in the circuit between the balls reaching the bottom and their transfer to the cart, as the balls did not stop at the end of the ramp due to their inability to enter the box. Instead, they were going over and leaving the playing area. However, it was deemed that this would not impact the overall evaluation of the toy’s functionality, as this disruption already existed in the circuit and represented the time needed for the child to move the cart from the start to the end of the ramp. It merely required the caregiver to return the balls to the top of the last block while the child performed that action and would not directly interfere with the flow of play. The set was thus considered coherent, and the circuit intuitive and functional. Overall, the appreciation of the resulting prototype was positive.
Figure 30 below presents the result of assembling all parts of the toy.
With a full-scale prototype and encouraging results obtained, the next step was to test the toy with a child. Access to a visually impaired or blind child was not possible then, so the test was conducted with a sighted child. Since the product is designed with special attention to blind and visually impaired children’s needs, it is recognized that testing primarily with a sighted child is a limitation of this study. However, it was considered that valuable feedback about the toy’s performance could still be obtained from a sighted child’s interaction with it. Future iterations of this research will prioritize direct testing with the target demographic of visually impaired or blind children to gather more relevant data.
The participant was a 3-year-old sighted child, who is able to follow simple instructions, engage in imaginative play, and interact with others. During the test, the child was guided by the adult, his mother, who takes care of him daily. Before this test, informed consent was obtained from her. The entire process was recorded to ensure all aspects of the interaction were captured. This allowed us to observe and analyze the child’s interaction with the toy in detail.
Figure 31, a frame extracted from the test video, presents the assembled toy set up in the living room, with the child engaging with it. The video is available on YouTube and its link is provided in the caption of the figure.
This test revealed a few minor issues in the product that required rectification. These findings underscore the importance of prototyping and testing in the design process. It is through such iterative processes that potential issues can be identified and addressed, leading to the development of a more refined and effective product. The specific issues identified, which have been outlined earlier, will be thoroughly described, addressed, and resolved in the next subchapter.
Thus, the prototype served its purpose by providing valuable insights into the toy’s performance and areas for improvement. These will be carried forward into the next phase of development. The next phase includes evaluating the issues found, their correction, and the creation of a new prototype. These steps are detailed in the following sub-subsection.
4.3.2. Adjustments and Second Prototype
This subchapter focuses on the next steps taken after testing the initial prototype. These steps include describing and evaluating the identified issues, designing and implementing necessary corrections, and producing a new prototype. The aim is to refine the toy based on the feedback and observations from the initial testing phase.
One such issue was the significant resistance offered by the cart, which impeded its smooth movement along the path, making it challenging for the child to push. This problem was effectively addressed by applying paraffin wax to the cylinders at the cart’s base, thereby reducing friction.
Another observation was that the mat pieces tended to separate slightly while the child played, as shown in
Figure 32. This led to minor disassembly and the creation of small gaps in the play area. This indicated inefficient fitting and posed a potential risk for children to pinch their fingers, for example. As a result, the fitting system was re-evaluated and redesigned from a half-circle to a ¾ circle shape to prevent the pieces from sliding.
Figure 33 illustrates both fitting systems to facilitate an easier comparison.
It was also noted that the balls could leave the mat area and fall to the ground if the child accidentally pushed them or bounced. This is an unexpected scenario that could lead the ball to unknown or unreachable areas for the child. Therefore, it was taken into consideration, and a solution was found. A proposal was made to add a level around the entire perimeter of the mat to prevent the balls from falling off when sliding.
This time, 20 mm thick agglomerated cork boards were available, but it was found that this thickness did not provide the desired and necessary resistance for a good performance of the mat pieces. Consequently, a decision was made to add a thin board of poplar wood at the base of the pieces. The previously added cork border was also extended in the opposite direction to conceal the wood’s thickness, giving the impression that the pieces were entirely made of cork (
Figure 34).
A new full-scale prototype was produced to evaluate the newly developed proposals. Since the blocks and the cart did not present problems and hence did not undergo any changes, these pieces were reused for the new prototype. Therefore, only the mat and the blocks with inclination were reproduced—the latter because they had unnecessary holes on their surface.
The enclosed pieces were produced first. This process mirrored the one previously described. Parallelepiped agglomerated cork blocks were cut using the sliding table saw. Subsequently, the saw’s angle was adjusted to create the bottom V-cuts, followed by making the upper cuts using the existing mold. The final stage involved manually sanding all the pieces.
Like the initial process, poplar wood boards were cut with the automatic panel saw. Next, the cork boards were also cut on the sliding table saw. However, the available boards only allowed the production of six full-size pieces out of the nine that make up the mat. To overcome this limitation, the remaining three pieces were manufactured using the leftover parts of the cork, composed of two cork halves that would be glued together.
Once the two materials were prepared, the gluing process began. Similar to the previous pieces, contact glue was applied to the surfaces of the cork and wood. They were then placed one on the other, pressed, and left to dry. In the particular case of the cork halves, they were also glued to each other on top of being glued to the wooden board. As shown in
Figure 35, clamps were applied to press the two halves against each other and ensure a good result, without cracks. After this process was completed, the pieces were left to dry.
The necessary cork strips for lateral application on the mat pieces were cut using a sliding table saw. Once the pieces were sufficiently dry, these strips were glued to them. A rubber hammer was used to ensure efficient bonding (
Figure 36). Completed with the application of the cork strips, the pieces were left to dry. The final step involved sanding and finishing the pieces.
Subsequently, all the pieces were assembled. At this stage, the ball set was already developed and prototyped. Therefore, the set included the ball set, substituting the previous large ones.
It was concluded that the system was functional and that the identified issues had been resolved. A new usability test was conducted with the same sighted child as before to verify this.
Figure 37 presents a frame from the video recorded during this new test. The video is available on YouTube and its link is provided in the caption of the figure. The testing phase validated the functionality and efficiency of the new design, confirming that all issues identified in the previous prototype had been successfully addressed. This marked the culmination of the development process.
This final prototype was showcased at the Cork in Science and Applications 2023 (CSA’23) conference in Vila Nova de Gaia on the 7 and 8 of September 2023. Furthermore, a detailed presentation was delivered, outlining the journey from the initial stages of development to the final result.
Full-scale prototyping and real-world testing were essential in bumpi’s development. The prototypes served as tangible representations of the concept and offered valuable insights into its feasibility and potential success. This process facilitated the identification and resolution of unforeseen issues, resulting in a more robust and user-friendly design.
The testing phase provided critical insights into the product’s performance and usability, uncovering areas for improvement that were not immediately apparent without hands-on interaction. The feedback from the sighted child was especially informative. It demonstrated that, while designed with a focus on the needs of visually impaired children, the toy can also benefit sighted children. The finalized proposal for bumpi will be presented in the next subsection.
4.4. How to Play with Bumpi
This subsection provides an analysis of bumpi’s design and functionality. It examines the composition of the toy set. Moreover, it discusses bumpi’s operational mechanics and its interactive experiences.
The bumpi toy is an innovative activity mat primarily crafted from cork. It is designed to stimulate the senses and foster motor skills development in young children, particularly those who are blind or visually impaired. The toy set comprises various parts—a mat, a ramp separated into blocks, sensory balls, and a cart—all designed to provide a rich sensory experience through sounds, textures, and movement.
The mat serves as the base for the activity and defines the playing area. It can be divided into nine smaller pieces for easy assembly and storage. The ramp, built up through buildable blocks, fits on the mat. Each block is designed to ensure a firm grip and safe play for children.
Figure 38 illustrates the steps of the child’s interaction with the ‘bumpi’ toy. Initially, an adult assembles the mat and places the child on it. Then, with assistance from the adult, children explore the toy. They become familiar with its textures and sounds—key elements designed to stimulate their senses.
The ramp, a key component of the bumpi toy, comprises several cork blocks. Three distinct types of blocks are used in its construction—the smaller block, the inclined block, and the box block. These blocks are stacked and assembled in a line, creating a height gradient. The inclined blocks are strategically placed at the end of each line, culminating in a box block at the end of the ramp. Once the ramp is assembled, it sets the stage for the child to start the play circuit.
The six balls, with different textures, contain small objects that produce sounds during movement. They are placed one by one at the top of the ramp. As the balls roll down the ramp, they bounce at various levels, producing a unique auditory experience for the child.
A cart is also included in the set. Once the balls reach the end of the ramp, the child pushes the cart along the path to collect them. This activity not only enhances their motor skills but also adds an element of fun as they can transfer the balls from the ramp to the cart and bring the cart back to the start for another round of play.
In conclusion, the bumpi toy set is a carefully designed educational tool combining tactile materials such as cork with auditory elements such as sensory balls that emit sound. Its main objective is to nurture the early development of motor skills in children while ensuring safety and enjoyment during playtime. By creating a safe and stimulating environment, bumpi meets the distinctive needs of blind and visually impaired children, making playtime both an enjoyable and enriching experience.