Switch adapted toys are expensive and the variety can be only determined by a few companies that essentially do what I have done here. Although like many toys last only as long as the kids are interested in them. As switch toys go this has it all for simple cause and effect. The vibration, motion and auditory stimulation are great. I have made lots,lots,lots of these and they fly off the shelves. They can be great cause and effect play, interaction and therapeutic toys for training kids with different mobilities!
Step 1
For this Instructable you will need the following:
1. Drill with 1/4 inch or drill bit
2. Glue Gun
3 Soldering iron and solder
3. wire strippers and two peices of small guage wire
4 Jelly bean Switch or similar to test your work
5. small electronics sized phillips screw driver
6. giggle pig, cow, dog or the like.
7. 1 female 1/8 ' mono jack port
Once a toy has been switch-adapted (as in this instructable), it can be turned on using any of a number of switches. Maybe the child can't press the little switch on the toy, but maybe they can press a switch that is 10" across. Maybe they can use a switch that they press by moving their head. Maybe they can twitch an eyebrow - there are switches that work with that. Point being, there are lots of different type of switches for various types of access. The industry standard is for such switches to terminate in a 1/8" male plug. This instructable shows how adapt a toy so that it can be controlled by such a switch.
my daughter has probems activating her giggling cow resorting to throwing it on the floor or asking someone to press its nose
I've been doing these mods for years for my daughter because the mark-up on the toys is ridiculous and the variety is slim, as you mentioned.
Keep it up!