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Jun 7

Missing B screws


I just got my kit today (huzzah!) I did not find any B screws in it though. So far, everything else seems to be there. The board with the shanks on it had tape, but I don't recall any blocks with the screws set in them. I just dove right in and started assembling, so I don't have any good pics of the raw pieces other than the attached.



Also, small bit of feedback - the sanding block was just a little too inadequate to sand all the pieces down for me. Can I just roll with 220grit sandpaper?


There is a green "2" written on one end of the priority mail box the kit came in.

Order #826

Jun 7Edited: Jun 7

It’s different in recent shipments. Mine is as same as yours. screw b was to be replaced by screw c, which is mentioned in the instruction.

Screw B are replaced by Screw C (with flat ends). Screw D are used for mounting servos, and their pointy ends are inside the robot body to avoid injury.

Jun 8

Ah. I wasn't sure if my kit was a 'later version'. I was able to finish construction. The instructions on just how to mount the main board with a raspberry pi aren't very clear - I could not tell if the board was supposed to be mounted to the underside of the back pieces, or on top. On top seems to work so far.

Yes, to the top side. Check out this side by side comparison. It's also shown in the written instruction.


New Posts
  • With writeinstinct.ino sketch loaded I calibrated joints, updated instincts, and calibrated the MPU6050 with no problems. When entering commands into the serial monitor all positions work and run great; sit, walk, rest and kbalance stands level with head and tail straight. The problem accrues after loading the main Nybble.ino sketch. Nybble works great with the remote control but on the balance command the body of Nybble leans to the right, the tail moves to the right of center and the head tilts down and to the right. The walking goes to the right quite a bit when testing with writeinstinct.ino loaded. The other positions look "true" when sitting, pushups, rest, butt up etc.. Also with Nybble in balance/standing position when pushing and or tilting Nybble to the right or left the right side goes over very easily while the left side has a more notable resistance when pushing over. It falls/leans easier to the right side and never will fall over to the left side. Front and back tilt work good with legs moving into the underbody position. No amount of calibrating the MPU6050 or servo angle adjustment has corrected this behavior. I have calibrated more than several times, even switched servos leg assemblies, looking for a really weak servo(s), to the other side but with no better results. I noticed when running the calibration for the MPU6050 in the serial monitor waiting for the "6 numbers", it has more than once brought up only 5 lines of numbers on the completed MPU test and the test at times took over 25 lines of numbers printed out in the serial monitor before the MPU testing was finished. ( lines of numbers like this; " -1390 2206 999 100 -8 8 " ) Is it possible that the MPU6050 gyro/accelerometer is failing ?? The NyBoard Version is V0_1 mounted servo wires side down with the FTDI connector to the rear of the cat and have been using 2 sets of EBL 14500 fully charge batteries. I have not modified the NyBoard to "Pro Version" as like on the forums. So far its been fun, Thank You for the great kit Rongzhong & Team Members! Any help would be greatly appreciated !
  • Hello, is it possible that i have somehow flipped left/right position on sensor ? When i lean nybble to left it is not trying to compensate but moving even more left. Same for right. Front and back lean work as expected. Second question - is it normal that servo are moving with little delay after each few degree of movement - mean movement is not smooth but with delay intervals in it. Is it by purpose ? Is there any way how to fix / change it ? For example higher quality servos ? thanks
  • Hello, i have an issue with calibration. I have new kit with v2 board, original servos. Batteries are ok, measured and fine but i did try external laboratory power supply as well but without luck. First, i did basic calibration with "c" on serial console and set basic leg angle as on following picture: Them i start to calibrate using command "c8 number" to do fine tuning. Servo 8 and 9 are acting weird, when i send "c8 0" several times ( mean i will send same command over and over ) servo move to random position: This is happening only to servo 8 and 9. Servo 10 and 11 works fine mean command c10 0 will not move servo at all and c10 1 will move it little bit. Multiple same commands are working fine too. Next weird is when i reset serial connection akka restart main board and send command "c" for basic calibration position all legs move to correct position. Any suggestion before i will start some deep debug action ? :) Thanks