Just to be clear for our new RSV2 owner, there is only one motor that controls the head and hands. When the head rotates to look to the left, the left hand should open. When the head rotates to look to the right, the right hand should open.

If the head rotates, but the hands don't open, then there is something wrong with the rack and pinion gearing that tugs on the hand cables.

If it comes time to open up your RSV2 and look for the trouble, there are pictures of what to look for in some other threads here in RoboCommunity

http://www.robocommunity.com/forum/thread/13081/need-some-help--------------/?

ScottE -- Member (always) & Moderator (when needed)

Opening him up was not going to be the first thing I suggested, exchanging him was. I would only recommend opening him up if your warranty had expired.

RoboGuide - Your guide to hacking all things WowWee

Actually we both mentioned it, and yes, that is for every scenario. They are mechanically linked. The hands cannot open without the head turning. The head cannot turn without open a hand (unless its broken).

RoboGuide - Your guide to hacking all things WowWee

No, I would say you have one problem. The hands don't open. While we could speculate as to the exact cause of the other effects your are noticing, it would be purely academic and somewhat pointless (unless you are planning on attempting to repair it yourself).

RoboGuide - Your guide to hacking all things WowWee

Everybody destroys the box, I've never heard of anyone having trouble returning it because of that though. Taking a screw driver to your V2 will almost certainly violate your warranty.

You can see what the inside of the chest looks like here. Notice the two springs in the foreground, these are providing the force that keeps the hands closed. When he turns his head, a tab in a track (not visible here) should be pushing the plastic piece the relevant spring is attached to towards the outer edge. This allows the hand to open.

Since this is not happening, something in here is broken. The most common cause is as Mr Scott mentioned, a broken gear. These are not easy to replace, since the only source for them is either another V2 or Wow Wee (at least one person I know of convinced Wow Wee to send them a replacement gear).

RoboGuide - Your guide to hacking all things WowWee

My RSV2 has a similar problem but it is related to the head movement. He has trouble turning his head to the right (my left) and, as a consequence, his hand won't open all the way. If you grab the remote and move his head from left to right, when his head gets about half way from looking straight ahead and to the right he has a momentary break in the motion. He sometimes does the entire sweep form left to right but the movement "stutters" about 2 or 3 times. Other times it'll stop altogether and I have to have another stab at the remote. It's like the command to move his head is interrupted or the head itself is getting stuck, though the motor doesn't sound like it is straining. This is probably of no help to you all though is it?
As a result of this I've changed his name from Steve to Lefty

I started with 2 robots but before I knew it, well, it's a disease I tell you.
RSV1, RSV2, RS Media, Homersapien, Spidersapien, Roboraptor, Robotyrannus and Roboquad

It doesn't sound like a standard stripped gear, I'd look more towards a fault sensor or wiring.

RoboGuide - Your guide to hacking all things WowWee

It ought to be fairly easy to tell the difference between the two potential causes. If it's a mechanical problem like a bad gear, the motor will be working continuously. If it's an electrical problem, the motor will be cutting out.

If it turns out the motor is cutting out, it's likely going to lead back to a mechanical problem one way or the other. A loose piece may be causing the motor position sensor to give bad feedback to the robot. Or a wire may be getting strained and creating an intermittent open at a given position.

Bad gears have been known to cause the hands to begin to close, then snap open again as the missing cog tooth rolls around, and the rack backslides.

Here's a thread link that shows pictures of debugging a hand problem.

http://www.robocommunity.com/forum/thread/11481/Problems-with-hands/#5207

ScottE -- Member (always) & Moderator (when needed)

Your forgetting the joint is spring loaded (ie, it should snap back to center). Stripped gearing should also manifest somewhat on both sides, not just one (excepting damage to the rack). That's not to say it can't be a damaged gear, just that it lowers the possibility.

RoboGuide - Your guide to hacking all things WowWee