Phoenix Kit Build Questions

[Kai]

Hi there, I just bought the phoenix hexapod kit (so excited I squeeled when it arrived) and I've been taking stock of the parts and reading the assembly instructions and there is one thing I'm not clear on.

The kit ships with 18 Aluminum Servo horns. I am assuming these are to replace the plastic horns that are on the servos now. However the instructions hint that if you replace the horns you need to make sure the new horns are aligned "correctly".

There are no markers or numbers in the Aluminum horns like there are on the Plastic ones. Is there a hard and fast rule for aligning then correctly? The 4 holes are vertical and horizontal? I just want to make sure I get it right before I assemble then find I have to take the whole thing apart again because I did step 1 wrong.

Cheers!

Kai

[tom_chang79]

hello Kai, welcome to the world of robotics!

First, to center the servo horns, you need to hook up the SSC-32 and the servos and do a "ALL=1500" command (it's a button) on Lynxterm (available free off of Lynxmotion's .com site).

Once you have the servo centered, you then need to make sure that all the horns are "aligned" for this center point. Make sure that You have two holes straight vertical, two holes straight horizontal with respect to the servo casing...

Don't worry if teeth in the Servo horns doesn't EXACTLY line up the threaded holes in the horn vertically or horizontally, you will most likely make some fine adjustments once your phoenix is assembled. I know I did, I know many other have also, and I don't know if anyone has all 18 servos exactly lined up without fine alignment (called trimming) later on.


What I mean by fine alignment is, after you put your horns on as close to "center" as possible. The true center of the servo horn might be at pulse width of 1525 instead of theoretical 1500...

[Kai]

Thanks very much or the reply! I've started assembly and I'm having a ball. Fingers are sore from all the small screws... but enjoying it.

I do have a further question tho. I've gotten to the SSC-32 portion of the assembly and I notice a couple of points where the posted instructions differ from what I actually have.

I note for example that I have 2 x cables with a connector for the battery pack and a switch inline.

I also have 2 x battery packs. But the instructions seem to indicate only one of those cables being plugged into the SSC-32 and make no mention of mounting the battery pack at all.

Do I use both battery packs? Do I cable both into the power in point on the SSC-32?

They also show a switch wired into the 9v board power cable that is not present in the 9v cable I have.

Actually now that I think about it I also got 2 x 9v cables as well. I assume I don't need the second as the bot board feeds off the power feed from the SSC-32?

Thanks in advance.

Kai

[DresnerRobotics]

You've got a couple options there:

You can power the logic (make sure to set the jumpers to isolate Vin and Vlogic) separately using the 2nd 6v nimh battery, or you can use the 9v connector and power it via 9v battery.

For servo power, use the 6v battery pack of course. If you choose to power logic with a 9v battery, you have the option of using the 2nd battery pack as a spare, or wiring it in parallel for double the runtime.

We ship the kit with 2 batteries for these reasons.

The two switches are for each logic and servo power, if you choose to use the 6v nimh battery pack for each. If you want to talk about it further, feel free to give me a call, numbers at the top of the page

Tom- great post, +rep!

[Kai]

ahhh thanks.. that makes a bit more sense.

If I decide to go 9v for the logic on the SSC-32 and on the Bot Board 2 I assume I can power them each via their own 9v if I wanted as opposed to the passthrough as shown in the online instructions?

Also if I wire up both battery packs to the SSC-32 do I wire them both into VS1 or one into VS1 and the other into VS2?

EDIT : oops, for clarity I mean if I want to power the servos with both Battery packs above.

Thanks again.

[Adrenalynn]

Powering servos from a 9v battery would be exceptionally not recommended - assuming you don't like the ozone-ish smell of burnt electronics.

You want the 9v going in to VL on the servo controller and to power the BotBoard. You need a 6v battery going to the servos.

That's too many servos to run off the onboard regulator by a loooooong shot. Two, maybe three small servos max.

[DresnerRobotics]

ahhh thanks.. that makes a bit more sense.

If I decide to go 9v for the logic on the SSC-32 and on the Bot Board 2 I assume I can power them each via their own 9v if I wanted as opposed to the passthrough as shown in the online instructions?

Also if I wire up both battery packs to the SSC-32 do I wire them both into VS1 or one into VS1 and the other into VS2?

EDIT : oops, for clarity I mean if I want to power the servos with both Battery packs above.

Thanks again.

You can power the SSC-32 and Bot Board from separate 9v batteries if you choose so, or power them both from the same, depending how you wire it. Make sure the VL=VS jumper is disconnected though.

As long as VS1 and VS2 are jumpered to be connected, you can connect a battery to each terminal, which will take care of your parallel connection. Likewise, you could wire the two batteries in parallel via a splitter and run them into VS1.

[jes1510]

One more thing about the separate power supplies; servos are extremely power hungry. Servos can need a pretty good amount of current when they are loaded and if your battery pack isn't up to the task (high internal resistance) then it can cause power fluctuations on the power bus. That can cause all kinds of funkiness such as microcontrollers resetting etc. It's almost always a better idea to run motors off of one power supply and the electronics off of another.

[Kai]

Once again.. thanks for all the really helpful replies. So I've taken a photo of my understanding of a pretty ok setup. See the attached file. Is this ok or am I going to melt something?

I'm going to power the logic off 1 x 9v and the servos off 2 x 6v.

I have 9v plug connected to VL on the SSC then a pair of wires carrying that up to VL on the bot board as well. I have VL-VS unjumpered on the SSC.

I then have one of the 6v batter pack plugs wired into VS1 and the other into VS2.

VS1=VS2 are jumpered on the SSC.

On the Bot board I also have a jumper on VS-VL which I'm unsure about. In the online schematics it's shown unjumpered but I'm unsure how voltage get to the PS2 controller without it?

Also my board shipped with the jumpers on VS-5v for each of the pinouts in the same row as the PS2 controller on the BB. Also not on the schematic... these need to come off?

As well as the jumpers on DAT CND and ATT? (also not shown in the schematic but on my board as shipped)

And last thing.. in the online instructions there are two schematics for the SSC-32 and one shows both jumpers in the "BAUD" area connected and the second only show the first one (left to right). Which is correct or are they different stages in the setup?

*phew* I think that should about do it. Thanks everyone for your help! I'm a really cautious type and while I think I have it sussed I want to be 100% before applying power.

[tom_chang79]

well, the VS=VL jumper works the same way as it does on the SSC-32... It's basically the jumper to see if you want to power the on-board regulator for the Logic circuit (microchips, microcontrollers, etc.) off of the VS (servo power) rail...

If you're tapping into the BB2's VL directly from SSC-32's VL (which is what I do too), you can take that jumper on the BB2, VS=VL off...

As for the DAT CND and ATT, unless you're planning to use the PS2 controller for it, you don't need to touch those... As for the PS2 controller, I have no experience with it...

You're on the right path, you're almost there!