Question
Asked September 5 2015

Community Question

Hello,

I just got a Six Hexapod a couple of days ago. Everything worked fine for the first 2-3 days, recharged the robot when i heard the battery reminder (after waiting a while for the battery), etc. wifi, remote control, etc. was all working nice and everything.

The other day is was shooting a video and the robot's moves were jerky. The motors would start a movement, then stop for a couple 100s of second, then start again very fast (as if trying to complete the movement as fast as possible). Surprisingly it was more noticeable when moving slowly than when moving fast (keyboard control from EZ Builder). I suspected wifi latence (even before i read https://www.ez-robot.com/Community/Forum/Thread?threadId=8173), did a bit of netsurveyor wifi diagnostics and changed channel (but still same problem and i have a very good signal).

Then at some point, the robot stopped mid-move and seems entirely unresponsive. I tried the following:
- turning it off and on back again
- waiting for a while, recharging the battery and trying again
- removing all cables, leaving just the board on the body and trying again

It doesn't light up, make any sound, move or anything else.

Battery seems ok (i have the blue charger, red led when connected to power outlet, green led when connected to battery, green goes off after a while when charged, etc.) but the board seems dead.

Any ideas of what is going on and what i could do to test different scenarios ?

Regards,
September 6 2015
I was using the Six Example Project (walk forward or fast walk forward i don't remember exactly whih one).

How many servos is too many on this board ? If i add claws for example on my Six, does it mean i just have to watch that all servos are not running at the same time ?
September 6 2015
It's not the board but the ability of the battery to deliver enough amps to the board. With the lipo that is in the robot, you are fine with moving all of them in quick bursts like the stand up reutine. Constantly moving all 12 at the American time could cause an issue. The walking uses 6 at a time I think.

I would check binding cables to the servos as Alan suggests.
September 9 2015
After hunting for the right fuse (one shop only had 15A, the other only 25A), i finally got a couple of 20A fuses. Put them in and it boots up again (cool).

But... i still have the jerky motion (which i am sure i didn't have the first few days). I tested with both AP Wifi and Client Wifi. Good wifi conditions in both cases, same room, laptop less than 2 meters away, wireless router less than 3 meters away, etc. In that room, with my smartphone on wifi, i get a stable 150mbps download and 110 upload speed.

I made a simple test routine, one servo, 2 frames between 10 and 170 degrees and it stops and starts again very often. See videos below:

Fast movement
0.01, stalls when going up
0.11, stalls again when going up (longer)
0.16, takes longer than usual to reverse
0.20, stalls twice when going down
0.26 longer stall when going down
0.31 stalls going down
0.41 stalls going up
0.46 stalls going up
0.51 stalls going up
0.56 stalls longer going up
1.01 stalls before reversing
1.06 stalls when going down

Slow movement
0.56, mega stall
+ lots of smaller ones

Any idea what could be causing these stalls ?
September 9 2015
@d.cochran @thetechguru Regarding freedom of movement for the servos and wires, as you can see in the videos, it doesn't seem to be the problem, although i must admit it hurts my eyes a little bit to see the wires sticking out of the back of the servo and touching the back of the holding plastic thingy. If it bothers me too much, i will someday have someone print me parts with a larger comfort zone behind the servos so as not to feel pity for the poor cable at every movement :-)
September 9 2015
Note: if i should open a new discussion since i can't change the title, please tell me.