Sara Oliver, Jason Williams, Bryan Kirsch
In partial agenesis of the corpus callosum, the corpus callosum does not fully develop. Our client, a three-year-old girl with this condition, exhibits difficulty with muscle coordination, fine motor skills, and body awareness. She works with therapists on put-in tasks to improve in these areas. Commercially available put-in toys are too challenging for her and do not provide enough feedback. Our goal was to design a device which met the client’s current abilities, provided positive feedback and prompting, and helped her to improve her muscle coordination, fine motor skills, and body awareness. We created a put-in toy which uses RFID-tagged objects that trigger audio and visual feedback when placed into the box and which has ways to increase the difficulty level to promote continual growth in the target areas.
In order to properly coordinate movement, the left and right sides of the brain must be able to communicate with each other (1). A giant pathway called the corpus callosum connects the two hemispheres of the brain and allows for this vital communication to occur (1). However, in less than one percent of the population, the corpus callosum does not fully develop during gestation leading to a condition termed “agenesis of the corpus callosum” (2). People with agenesis of the corpus callosum may exhibit a wide range of symptoms. These can include poor muscle coordination and delays in reaching developmental milestones such as walking or talking (1).
Our client is a cheerful three-year-old girl with partial agenesis of the corpus callosum. She works with physical and occupational therapists to improve her fine motor skills, body awareness, and muscle coordination. In particular, the therapists use a “put-in” task to work on these two goals. The put-in task involves the client picking up an object and placing it inside a container set on the table. At the current time, the client cannot use commercially available “put-in” toys such as the Growing Baby Elephant Shape Sorter (Figure 1) because she lacks the ability to raise her hand high enough to put the toy in and is not able to distinguish and sort shapes yet (4). Typical put-in toys have holes smaller than 2 inches in diameter while the client is presently working with holes several inches in diameter.
Currently, the client is able to complete the task using a 9 by 6 by 2.5 inch tray with the therapists providing verbal encouragement and direction. The therapists may also need to prompt the client by touching or moving her arms. In order to accomplish the put-in task, the client needs the help of at least one other person. This requirement considerably limits the amount of time the client can practice this task. The therapists would like the client to be able to work on this task independently, at home or in the office, while still receiving positive feedback with a “put-in” toy appropriate to the client’s physical abilities.
The goal of this project is to design a “put-in” device which enables the client to improve her fine motor skills and body awareness. In order to encourage the client to use the device, the device will incorporate positive feedback and be designed so that the client can play with the device without assistance from the therapists or her caregivers. The device design will include a method to alter the difficulty level of the task in order to promote continual growth in the target developmental areas. Such alterations for difficulty may include adjusting the height of the put-in box or the size of the hole. The device must also be safe and enjoyable.
DESIGN & DEVELOPMENT
The client will drop an object into our device which will then detect the object and provide feedback specific to that object. Our device has six key components: a box with an inclined slide inside, objects suitable for the client to grasp, a detection mechanism, a microcontroller, feedback mechanisms, and methods by which to increase the difficulty of the task. Figure 2 shows the device just prior to final assembly.
The box itself measures eight by eight inches and is three inches high with a three by six inch rectangle at the back which provides the form for the display. The slide is set into the box at an angle of approximately twenty degrees. Figure 2 shows a view of the box. The slide is coated with a polyethylene film which increases slide’s slipperiness. The box itself is made of acrylic.
For objects, we decided to make stars, hexagons, squares, and triangles. They are approximately 2 ½ inches in diameter and half an inch in width. Shapes are provided in three colors – red, green, and blue. The objects are made of acrylic with the RFID tag inserted in the middle.
For the detection mechanism, we have chosen to use radio-frequency identification, RFID. Tags are placed inside the objects which can be picked up by the RFID detector, an ID-12 RFID reader from ID Innovations. The RFID detector is placed underneath the white slide with a custom made antenna fixed near the outlet where the objects exit the box. The objects are registered as they slide over the detector.
Microcontroller & Feedback
The detector then sends a signal to the microcontroller, an Arduino Uno. The Arduino triggers the appropriate feedback for the specific object. The feedback may be either audio or visual or both. The audio feedback is provided by a Rugged Audio Shield through a speaker. The visual feedback is provided through a light-up display of shapes located on the box. As an example, if the object is a red star, the feedback may be an audio clip of the therapist saying “Good job, you put in the red star” as the corresponding shape lights up in red on the box. The movie below shows an earlier prototype of the device in action. When the star slides down, it’s tag is registered by the RFID reader and the red LED is turned on. When the triangle is inserted, the green LED is lit.
Methods to Increase Difficulty
Several methods are available to increase the difficulty of the put-in task. The first one involves the use of multiple, interchangeable tops. These tops have holes ranging from seven inches in diameter to four inches with one top cut with shape-specific holes. Difficulty can also be increased by a change of mode. The easiest mode simply responds to whatever object is detected. A harder mode is available which asks the client to choose a specific object to put in. Extra RFID tags are provided to enable the therapists and caregivers to record responses for additional objects, opening up possibilities for advanced choice-making tasks.
The device is powered by a rechargeable lithium ion battery. A charger is provided with the device. A small LCD screen displays mode and option information during setup. A microphone is built into the device to enable the therapists or caregivers to record audio for the custom tags.
Simple: Device responds to whatever shape is put in.
Choice: Device prompts user to put in a specific shape. Appropriate feedback given if choice is correct or incorrect.
Record: Allows therapists/caregivers to record new audio prompts for objects using spare RFID tags.
Random/Pattern – user selects if objects prompted are randomly selected or asked for in a predetermined order
Color/No Color – user selects if shapes are also identified by color
Built-in/Custom: Built-in – prompts and responses are pre-programmed (associated with provided RFID-tagged shapes) ; Custom – prompts used have been associated with new objects selected by the therapists/caregivers
Audio On/Off – allows user to turn on/off the audio feedback and prompting
Lights On/Off – allows user to turn on/off visual LED feedback
The device was evaluated to determine if it was a useful put-in toy for improving the client’s fine motor skills, body awareness, and muscle coordination while being specifically adapted to the client’s needs. It was also evaluated to determine if it was portable, safe, able to provide multiple difficulty levels, and engaging for the client. The device was tested by the designers, the client, and the client’s physical therapists and evaluated against the design specifications.
The physical therapists evaluated the device against other put-in devices and declared the device superior and useful because it meet the client’s needs and provided feedback. The client was able to use the device mostly by herself with some additional verbal prompting from the therapists. Once the client is accustomed to the device, it is hoped she will no longer need outside prompting.
For portability, the device weighs less than five pounds and runs off a battery. For safety, all electronic components are sealed inside the box and isolated from any contact with the client while the RFID tags, a choking hazard, are permanently sealed into the objects. Multiple tops and modes, as described in the design section, do provide several levels of difficulty. The light display and speakers worked and provided visual and audio feedback. The client responded positively to the feedback by smiling and seemed willing to continue to use the toy. Overall, the client appeared to enjoy playing with the device, saying it was “Fun.”
DISCUSSION AND CONCLUSION
The device provides an engaging tool for the client to use to improve her fine motor skills and muscle coordination. The total cost of the device was at budget, approximately four hundred dollars; the most expensive component being the acrylic. The device design is appropriate to the client’s current abilities but is able to make the put-in task more difficult as the client progresses. The client liked using the device. The therapists believe the device will be useful, not only to this specific client, but to other children who have similar limitations.
1. National Organization for Disorders of the Corpus Callosum, “Corpus Callosum Disorders,” 2009, accessed 5 February 2013, < http://www.nodcc.org/index.php?option=com_content&task=view&id=12&Itemid=27>
2. Caltech Corpus Callosum Program, “Information and FAQ’s,” accessed 5 February 2013, < http://emotion.caltech.edu/agcc/info.html>
3.Travis Research Institute, “Mental and Social Disabilities in Agenesis of the Corpus Callosum,” accessed 5 February 2013, < http://www.travisinstitute.org/acc/>
4. Fisher-Price, “Growing Baby Elephant Shape Sorter,” accessed 5 February 2013, < http://www.fisher-price.com/en_US/brands/babytoys/products/63358>
We would like to thank our client and her family for allowing us the opportunity to work with them. We would also like to thank Jennifer Radzik and the other members of her team for their time and advice as well as for their patience and encouragement. Our TA, Sunny Kasoji, deserves a round of applause for being our go-to person throughout it all. Finally, we could not have completed this project without the support of our professors, Dr. Richard Goldberg of UNC and Kevin Caves of Duke. Funding for this project was provided by National Science Foundation grant # CBET 0966571.
12421 Verandah Blvd.
Ft. Myers, Florida, 33905