Need relays / switching

I note in another thread there is a mention of adding switching to the pololu units.

I like many others use a combination of servos and switched devices.

On the 8 servo unit, I am using 4 servos and 4 individual RC E-switches.
In addition to that, I need to add relays to each of them (they are opto isolators) with a transistor driver.
2 of them have to be bidirectional voltage.

I am going to try another that seems to have a relay on it already (Dimension Eng pico switch)
But Ill need to plug in 4 of them which makes it costly at about $20 a switch, and bulky with 4 of them, the pololu and modem.

If the pololu could have 4 servo outputs and 4 E-switches with small relays instead of 8 servos it would save me a load of time and money.
If the relays are an issue I could make them on a seperate board with drivers to plug into the pololu switched outputs.

If you would be prepared to make a batch of these type servo driver boards (4 servo, 4 switched), Ill take 40 of them, yesterday !, prepaid order if you need.

I am certain others would use them if you made them.



We are definitely planning on coming out with some more capable servo and general I/O control boards, but that probably won’t happen for at least a few months. It sounds like you are already looking at spending $4k with you current approach, which we should be able to beat with a custom design for you. It would take about 4-6 weeks to get you the 40 units, and we might be able to expedite it some. If you are interested, please contact us with the specs you need (e.g. relay voltage and current) and when you would need the units.

- Jan

Hi Jan

Thanks for the reply and info.

Ive sent out the first few units with the servo drivers boards.
Customers are lovin it.
One of them had the old system from 2 years back and appreciates the new software driven units to the old RC driven one the most.

I bought 10 of theses E switches to see me through for a little while last week. (dimension eng)
I just used up the old E switches I had. (SpartanRC dual switch, discontinued)

The old ones above were a Dual switch, the first switch was 2 stage with 2 opto outputs
The other a single throw with NC and NO opto outputs
(Both switches servo output driven.)
To these switches I have been fitting 2 mini 5v relays and transistor drivers, piggy back on the board with hot glue, not pretty.

The reason for that was not load over them, but the need for birectional current flow which the opto otuputs could not do.
So for my switching needs, there is 500mA on one switch used in the latest units, the others are in the 10mA range.

The new rig uses the dual switch and one extra single switch.
The dual handles the 10mA switching on both.
The extra one I add now handles the 500mA load.

With the old E switches the 2 stage was driven off one servo output.
I intend to replace this with 2 individual switches.
So instead of the 2 stage and the single one one board, plus the other individual switch
For simplicity and now having more servo channels to use than before, Ill use 4 same single switches for the purpose.

So with the 8 servo drivers I drive 4 servos and 4 switches.
2 of the switches are connected to NC outputs, the other 2 uses their NO outputs.

So the 4 switches I want need to have birectional current flow, and NC and NO contacts.
As I have run out fo the 2 stage ones now in the first few units sold, Ill have to start using the indivdual single throw E switches for the same purpose, like I say it is not cheap at $20 each.
But these ones come with NC and NO relays on them and are compact. (dimension eng)

The issue of changing the servo outputs and commands sent when I changes these I can do in software, the bluetooth module that drives the pololu serial 8 board I flash with our product name and ver number so I can change ver with change of swithing arrangment and then detect that, to set which E switch set it has and use those servo commands for the right units.
(I have to be able to update software to all current owners.)

However if you produced a servo baord with the first 4 outputs for servos, the last 4 for swithing, that would be the replication of the 4 individual ones I am starting to use now, code wise, and saves me another optional block of code to use for variations in switches and which ouputs they come off…

So the request is
8 servo driver board as we have now, but the last 4 ouputs driving switches that have bidirectional current flow and NC and NO outputs.
I presume this would involve fitting 4 mini relays to the last 4 ouputs on the 8 servo pololu board maybe, that would save me doing it.

As to when I need them, sooner the better.
Ill order 40 of them, let me know where to pay and how much.
Il send a basic schematic for it.

Thank’s again