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Canada
Asked — Edited
Resolved Resolved by DJ Sures!

Intermittent Disconnect Of Ez-B From Ez-Builder - Too Frequent

Hello all,

I have an issue with a frequently intermittent disconnect of my EZ-B from EZ Builder. I am constantly forced to reset the EZ-B or my bluetooth connection or both. Sometime, I am able to operate for a good 20 minutes (+/-) before I am forced to reset, and other times I have to reset every minute or so (especially after issuing servo commands)

Some background:

This is a Wall-E project. I am inserting the EZ-B and the battery pack into Wall-e's "gut". However, they are not firmly attached and may move around slightly as Wall-E moves. Can this be a problem? Should the board be firmly attached? (I will eventually make sure everything is firmly attached and connected but I haven't finalized the Wall-e hardware configuration yet and wanted to do a few trial runs before)

I should also point out I am running Windows using Parallels on my Mac. I suspect this virtual os problem may be the main suspect. However, I am hopeful it is not the case, and someone else has experienced a similar problem and found an alternate solution for it.

Many Thanks for any feedback,

Sam

P.S. I am considering installing Windows directly using BootCamp (instead of virtual environments). This way I can start my mac using Windows as my operating system. It's just a pain doing so, as I would have to shutdown and restart every time I wish to alternate between OS'es

#1  
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.
Canada
#2  
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.
#3  
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 ?
#4  
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.
#5  
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)
Canada
#6  
@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 !
#7  
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.
#8  
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.
Canada
#9  
@ robot-doc ... I never understood why I need a bluetooth dongle if my laptop is already equipped with one (my macbook has bluetooth) ... is it possible to simply use that?
#10  
If you can check to see what class your internal BT is on your laptop. To get the proper connection and coverage you should match up your classes. Chances are you only have a Class 2 on the laptop. Class 2 seems to be very common. Also I noticed I got a steadier connection with a Dongle then the internal laptop Bluetooth. Just make sure your using the Microsoft BT stack.
#11  
As dschulpius mentioned, your computer probably only has a Class 2 bluetooth since most accessories that are made to work via bluetooth and PCs are units like keyboards and speakers with a need for a very short operational distance <= 33 feet.
#12  
I realize I'm jumping in to help late but yes I suspect that virtually running windows can cause some problems with a native windows app. So i would do like you suggested and do a full native install with correct drivers and default blue tooth stack. That's your best bet for reliable connection. Also a side note the V4 comes with WIFI built in and longer range. Upgrading to a wifi enabled board will also improve overall signal strength.
PRO
Synthiam
#13  
What is the error message when it disconnects? You can press the copy button on the debug window at the bottom of the screed. That will help me know what's up:)
Canada
#14  
Happy New Year Everyone !

@DJ Sures

When I first start up everything. Connection is made. I ask Wall-E to wake up ... and back to sleep ... then wake up again ... (that makes him move his head up with arms when he wakes up and then head down with arms down when he sleeps)

However, when I ask him to "Wall-e Go" (which makes him move forward, while moving hands up and down and moving head sideways left and right - all simultaneously) he moves forward and then I get a comm fault. EZ-B disconnects.

I ran the debug window the entire time and made a copy. Here it is:

Attempting connection to COM3
EZ-B reports EZ-B Firmware V16
Connected
Comm Err: The operation has timed out.
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 1

Received:
Disconnected
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected
Comm Err: Not Connected
BbytesToExpect: 0

Received:
Disconnected


AND THEN WHEN I ATTEMPT TO RECONNECT WITHOUT RESETING EZ-B, I GET THE FOLLOWING:

Attempting connection to COM3
Comm Err: The operation has timed out.
BbytesToExpect: 1

Received:
Disconnected
Connection Failed: System.Exception: Controller Not Responding
at EZ_B.EZB.Connect(String hostname, String tcpPassword)
Disconnected


__________________

At this stage all I could do is reset the EZ-B and start over. I am also sometimes forced to reconnect my bluetooth dongle by physically removing it and inserting again.

I have not yet installed Windows natively. Still running Parallels.

Will attempt to install Windows natively very soon and report back my results.

In the meantime, if that debug message tells you anything that may be of help, please let me know.

Thanks

Sam
PRO
Synthiam
#15  
Sounds like the batteries cannot provide enough voltage. Soon as the robot moves it uses more power. How many batteries does your walle have? Are they rechargeable?
Canada
#16  
@DJ Sures

That was it! Your suspicions proved correct. I replaced the batteries and problem resolved. I will monitor a bit longer and see if it comes back. I should've picked up on it as it was happening a little too much the last couple of days.

I am using 5 x 1.5 Duracell batteries. No rechargeables.

Do you have recommendations for a better source of power? lasts longer with enough amperage.

Thank you DJ Sures !

Sam
#17  
@ Sammy , a lithium ion battery pack. They have longer runtime durations for the size of battery and they handle higher current demands as well.