RePlay For Kids is a Cleveland, OH based charity that modifies mainstream toys for children with disabilities. Since many electronic toys utilize activation switches that require a level of dexterity that not all children have, Replay modifies the toy to add a more accessible switch in parallel. This not only provides local organizations with toys for disabled kids at no cost, but the toys are not limited to the few that are specifically designed for special needs use. A child can have the same popular “Tickle Me Elmo” toy that other kids rave about thanks to Replay's customization.
Usually the customization is relatively simple. A workshop volunteer will open a toy and find the activation switch for the toy's coolest function. Wires are soldered to the switch and left dangling outside of the toy. The wires are then terminated by a 3.5mm receptacle, where a child's switch can be plugged in to effectively add a switch in parallel. Each child has their own activation switch that is customized to their specific abilities, and may be activated with a large button, a bend switch, or even a blow switch. The 3.5mm plug interface is standard in the industry, easing broad integration.
Recently the toys have been getting more complicated. Sometimes a switch is a DPDT and needs to activate two functions at once. Other toys have lots of basic functions that could be made more interesting by activating several switches in a sequence. In the search for lower price points, some manufacturers design switches without ESD protection and pipe directly into a microcontroller's input, making for a short toy life when that wire is left exposed to the user by RePlay's customization.
To meet the challenge of ever-evolving toys, Replay has designed a simple, universal switch controller based on the MSP430. The design goals were identified as:
- Small size (~1 sqin.).
- Single Input, 8 outputs.
- Outputs are high or low true, depending on where wires are plugged in.
- Low power consumption for battery-powered toys.
- Can operate from 3-9V input power.
- Control of switches can be customized by loading different firmware
The initial design has been completed and thanks to OSHpark, the inexpensive boards have been built up for testing.
Future improvements include the following ideas:
- Make a few versions and have them pre-programmed to act as modules for easy use by volunteers.
- Make a miniature version for simpler toys.
- Make the PCB so it can easily fit in a project box.
Replay is only in the testing phase, but decided to open source the design to extend the potential reach of the idea. All design files can be found on there website, where they encourage comments and suggestions. And of course they are always looking for people in the Cleveland area to sign up as a volunteer!
