Thank you for choosing Thames & Kosmos and for your interest in our My Robotic Pet: Tumbling Hedgehog.
The reason that your hedgehog isn't rolling successfully is likely that the movement mechanics have become misaligned, probably due to the screws not being completely screwed into place (allowing the gears to separate slightly from one another). Other factors like using force to un-roll the hedgehog manually or some kind of impact. Here is how it should look under the shell of quills.
It takes some reassembling, but if you disassemble just the sides, it should only take about 15 minutes (or less) to reassemble it, since the outer shell is already built.
First, disconnect the shell from the arms that are holding it in place (pictures 1 and 2 below) and detach the head (picture 3):
Now, remove the shell by detaching it from the “neck:”
Disconnect the wires that plug the motor in the circuit board:
Now, unscrew and detach the following parts on the left side (and keep the parts you remove from the left side separate from the right, which you will be removing next:
Now, remove these pieces from the right side:
Now you can re-align the movement mechanics, following the steps starting on Step 6 on page 13 (through Step 22 on page 29).
Flip the hedgehog again so that you are looking at its left side and reattach the key-shaped piece (A7) to the body, pushing as far to the bottom as you can (replacing the screw and peg):
Now, place the long axle (P11 + D9) back in the hedgehog, making sure to line the raised peg on A7 to the groove in D9. Then attach A9 to D9, matching the raised peg on D9 with the groove on A9.
Repeat those steps on the right side and then reattach the shell, the circuit board, head and movement mechanics to the shell.
From there, starting on Step 6 on page 13 (through Step 22 on page 29), re-assembly is pretty simple, and it gives you the opportunity to re-align the movement mechanics.
Now try running the hedgehog on a flat, smooth surface by holding the button on its forehead for 2 seconds, pressing it 2 more times (so that its eyes turn green), letting it walk for a few seconds and then clapping loudly 3 times time (with about a half-second between each clap) just above its head. It should attempt consecutive rolls.
I hope that resolved the issue. If you have any other questions, please send an email to firstname.lastname@example.org and a member of our Technical Support Team will reach out to you.
Thank you again for choosing Thames & Kosmos. We hope you will continue to enjoy our products for many years to come.
The Thames & Kosmos Technical Support Team