Adaptive Toy - Snug-a-Bug Critter

The Snug-a- Bug adaptive toy project adapts the toy such that the functionality of pressing the toy's tummy can be triggered by the jellybean button. This allows children with motor skill or reflex challenges to be able to use this toy.

How the toy is manufactured to work: The snug-a-bug critter has a center belly button that triggers either a night song or day song to play depending on the switch setting when you push it. Each leg triggers a specific tone to be play such as Do, Re, Mi.

Materials:

1. VTech Snug-a-Bug Musical Critter Infant Toy With Light-Up Tummy
   
2. Jelly Bean Button, we used 3" from AbleNet
3. Sandwich Baggie
4. Electric tape
5. Zip tie at least 14" long and about 3/8" wide

Tools:

1. Phillips head electronics screwdriver, or some other very small screwdriver
2. Multimeter
3. Soldering iron/gun and solder
4. Wire Strippers
5. Drill and 1/4" bit, or something to cut a 1/4" hole in plastic
6. Needle nose pliers (optional)

Remove the electronics box from the back of the toy. Ours was zip-tied on, so we had to snip the zip tie loose before we could fully separate the box from the toy.

There are 4 small screws holding the back of the box on. Remove the screws and open the box. It is a good idea to put the screws into a baggie while you work. The clear button will want to fall out of the top also, set it to the side so it doesn't get lost.

Peel off the rubber cover on Button 1 (second image). Be careful to avoid damage to other parts of the circuit board while removing it. To test the circuit, use your multimeter to perform a continuity check. Turn off the toy. Set the dial on the multimeter to the "wifi" shape. When the probes are touched to a continuous circuit with the battery off, the multimeter will beep.

We found a continuous circuit with two ways to access it. The first is the little zigzagged rectangle inside the Button 1 square. The two sides of the zigzag do not touch, but are engaged when the black material inside the rubber button cover presses down on it. If you put your one probe on either side of the rectangle where the arrows are, there should be a beep.

The second way to get a continuous circuit is to put one probe on each of the metal-looking circles (circled in red in the photo). These come from the same place as the sides of the rectangle, but are another way to access it.

Completely remove the rubber Button 1 cover, if you have not already done so.

Snip off the audio jack from the jellybean switch. Use your wire strippers to peel off at least a half inch of wire, but not more than 1". Ours had an insulated inner core surrounded by a bunch of "loose" wires. We twisted the loose wires together, and made sure to keep them separate from the core wire. It was necessary to strip the wires in the core about 1/4" to 1/2", as well.

Feed a wire through each of the holes that used to hold the button cover on (denoted by yellow arrows). You will solder the core wire to one of the circles in the photo, and the loose wires to the other (denoted by red arrows). It does not matter which wire goes to which circle, we are just looking to attach the button so that it can close the circuit and make the toy play a new song with lights. The finished solder job is shown in the last photo.

Be careful to work quickly and precisely as possible; there is a coating of some kind that seemed to start melting a bit as we worked with it. Having two people made this step a lot easier. It's also worthwhile to practice a little bit to get the feel for how the solder melts and cools.

When the soldering is done, check the functionality of the button without disturbing the wire. It should interrupt whatever is playing and start a new song, with lights. If the toy is quiet but on, it should make the toy start playing music.

Cover all the solder and wire on the board with electrical tape to hold it securely in place.

You will need to safely drill or cut a 1/4" or so hole to accommodate the new wire coming from the circuit board. Once you have done this, route the wires through the expanded hole, and replace the screws. Note: to make the routing easier, we wrapped a little electrical tape over the original wire bundle.

You can ease the button box back into the bug's stomach, taking care that the black wire from the Jellybean Switch is not showing up inside the translucent part of the stomach. The wire should be fed out of the toy through the back. When the button is in place, use a zip tie to fasten the button box in place. We took care to put our wire under the zip tie, so it didn't get pinched (not pictured). All other wires should remain inside the toy.

There is a groove along the side of the box to hold the zip tie firmly in place; if needed, you can measure zip ties you have on hand to this groove to see if any work. I used pliers to tighten the zip tie a little extra. Fasten the velcro on the back again and you are done!