
I'm running a 12 volt 3 amp power supply. Then I have a 12 volt to 6 volt DC step-down to power my EZ-B4 and servos. After the robot runs a little while sometimes the servos stop responding. But most often If I run a script to put the robots arm on its hip, sometimes it will work. Other times the arms will start to move and then the EZ-B4 will disconnect and then reboot.
I have also seen that after running a while the servos in the arms will start to run slow and not quite make it to there assigned spot. While the servos in the neck keep right on going like normal.
So I was thinking we did not have enough AMPS for all the servos. See I have 2 servos in each shoulder, one servo in the elbow, two servos in the wrist and one in the hand for a total of 6 servos in each arm. + 2 servos in the neck.
Test 1
I started to look at the power supply. Maybe we do not have enough AMPS. So I grabbed one of R2D2's 12 volt 18 amp hour battery. R2 was not vary amused to see one of his battery's wandering off. While the servos ran a tad bit faster I soon ran into the same problems.
Any ideas? *confused*
And thanks Richard.
If you want sufficient power for servos, then a digital switching power supply is what you require - I recommend an ATX power supply from a PC.
Humm good idea on the ATX power supply. I seem to have a few of those kicking around.
Thanks.
Edit: could wire gage be an issue?
Also throw out the in line linear voltage regulators and get some Switching BEC's.
Castle Creations CC Bec 10A 6S Switching Regulator
Good Luck.
@dave I originally for my testing purposes had this set up with separate power going to these servos. This is the first time I have the system set up all thru the EZB. Since the d ports are longer regulated, I let the EZB power to be the same as the big servos at 7.4v then I have bec's on the 2 micro servos for the eyes. The jaw servo gets its regulated power from the audio servo control board. I think the length and gauge of wires might be my a problem too. Worst case I'll just set up the big servos on their own direct power from my line in and avoid putting that thru the EZB. I find it hard to believe with all the digital ports and the EZ servos rated higher than standard servos (6v I think) that mine would brown out with just two servos?!?
Here's the one servo mounted in the gearbox that browned out my EZB under load:
Electricity is very strange and will do strange things. My experience as a power distribution lineman who has been working on and repairing low voltage and overloading problems on a large urban power grid for almost 35 years now show me that overloaded wire can handle a lot of current. The voltage will drop some but usually it will heat up or melt. Under constant load the loading device will just keep pulling the current is needs till the conductor fails. More powerful devices like DC motors will rob current away from more sensitive devices like electronics if they are on the same circuit. In situations where there are low voltage problems on our power grid our engineers usually have us install larger transformers closer to the load. However sometimes we'll also upgrade the wire sizes if they are obviously to small.
Now startup load is a whole norther animal. This is probably what is causing the EZB brown outs. When the servo starts up the current demand spikes. If your feeding servo through the EZB the PS cant deliver enough current quick enough to keep the it up and running. This happens on our urban power grid also. When big industrial customers start turning on their motors and other current hungry devices the voltage on our distribution lines start to drop. We place large capacitors in line that switch on at times we know this will be a problem (like in the morning of a work day) to keep the voltage from sagging. We don't usually change the conductor size (unless it's a huge current draw like a fire pump), we just add ampacity. Our little servo, sensor and EZB circuits are much the same as a big city power grid, just smaller.
Sorry if I bored anyone. I thought this may be useful to this issue.
Particularly the bit about the high draw devices "robbing" from the low draw devices.
Alan
Thanks again and NEVER boring!
Castle BEC are great , but the cost is also very high as well, that being said mine are value focused for the budget minded hobbiest, student or child.
@Josh also has a great option too with his 3amp inline variable voltage regulators....
My problem is that my ez-b 4 is disconnecting, i have looked into nearly all the threads here and have upgraded to a lipo battery 2500mah so more than sufficiant power.
The strange thing is that if i open a new project the board connects fine and never cuts off, but when i load the JD project and try to connect it gives me the following:
Attempting connection on 192.168.1.54:23
Connected to 192.168.1.54:23
Reports EZB v4 OS With Comm 1
EZ-B v4 ID: 67-50-0-0-46-255-57-59-54-38-38-38
Setting battery monitor voltage: 7
Setting battery protection: True
Setting i2c rate: 300000
EZ-B voltage is 8.184497646
EZ-B temperature is 24.44489368264605312C
Connected
Comm Err: System.IO.IOException: Unable to read data from the transport connection: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags)
at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)
--- End of inner exception stack trace ---
at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)
at EZ_B.EZB.M3jweGrVXK(Int32 , Byte[] cmdData)
BbytesToExpect: 2
Received: 0 0
Disconnected
Can someone please help me out i am really giving up here it has been 3 days now *stress*
This is the battery i am using
I am on Windows 10 ent. 64 bit 64 gb Ram no antivirus running and firewall disabled
Check the cable to the JD Eyes and make sure it has a good connection.
Find the JD-No Eyes sample project and try that (or just try a connection with no project loaded).
If any I2C object tries to initialize and can't find the device, the EZ-B will lock up and disconnect.
Alan
Remove the rgb animator from the project before connecting to the ezb.
I think in the mean time i have found out the problem. i have a shorted servo. i disconnected it resetted everything and it seems to move without any problem.
Once again thanks for the help and again sorry for the double thread