Your servos may be drawing too much power from the EZ-B causing a brown out condition and a loss of the bluetooth connection. The hint is your statement:

"especially after issuing servo commands".

Try temporarily disconnecting a few servos or other things from the EZ-B if you can and see if that helps or eliminates your disconnect problem. You may need to power some of the servos from a separate power regulator.

Thanks for the feedback @RobertL184

the thought occurred to me - but the disconnect was happening even without servos running - admittedly not as frequently though. So maybe there is more than one factor at play here.

Then again I also thought that the EZ-B should be capable of running Wall-e's servos ? they're the same servos as per the kit and the movement is as per online videos by DJ Sures.

hmmmmm ... is there a way to calculate how many servos the EZ-B is capable of handling ? right now I would rather not invest in a dedicated servo controller board.

You can just use a separate battery to power the servos and still use the EZ-B without the need for a servo controller board.

One other question, how far away is the WallE from the PC ?

I've had the same issues with one of the 3 EZB's I have controlling my B9 Robot. I really think it's because of Bluetooth signal strength between the laptop and EZB module. The one unit that disconnects after receiving commands in located inside a steel case that's also unclosed in plastic and the other two only have to transmit through acrylic with openings to the air or thick rubber (the one behind the thick rubber also disconnects sometimes). When I place the laptop right next to the robot I have few disconnect problems.

The BT module on the EZB is only a class 2 which is a very week signal and only reaches about 30 feet (line of sight, through walls or other stuff like plastic it's less). I'd suggest replacing the BT module with a stronger class 1 that will push 300 feet. I was going to do this to resolve my disconnect issue but I have 3 new V4 EZB boards coming that connect through Wi-Fi.

Robot-Doc has replaced this BT Module successfully and has given recommendations on what to use and how to do it. Hopefully he will chime in again with a link to that thread.

You can order the class-1 Bluetooth HERE And while you're there you can order some header pins so that you can solder the header to the bluetooth and then just plug it into your EZ-B(3)

@Robot-Doc ... the intermittent disconnect happens even when Wall-e is right next to laptop. I don't think distance is an issue.

@dschulpius ... perhaps a weak signal is the culprit, and I may opt to purchase that class-1 bluetooth from Sparkfun. However, I was browsing the community forum and came across a discussion in which DJ Sures replied with the following:

" ... the ARC software runs in Windows only. You can install Windows as BootCamp, or use a virtual machine emulator, such as Paralellelelels or VMWare. We do not directly support virtual machine emulation because there are bluetooth issues with the emulators that we cannot control."

I am suspecting it's the fact I am using Parallel's virtual machine that may be the main cause of this issue. I plan on first installing Windows direct on my macbook using BootCamp and then monitoring whether the problem persists. If it does, then my next step is to update my bluetooth module.

I will post an update soon.

Many Thanks to all for your feedback !

You may be right. Hopefully using Windows directly will solve the problems.

At any rate if you continue to use the V3 EZB I think it would be a worthwhile upgrade to change to a Class 1 BT module.

Let us know how it turns out.

If at some point you do convert to a class 1 bluetooth on your EZ-B(3) also order a class 1 bluetooth dongle for the PC side.