My usual offtopic posting...enjoy

[Kermit]

Burning through those D cell batteries in a most UN-green manner. The youngest son loves his remote control Robotic Arm. The wifes i$$ue was quite clear to see. She even helpfully suggested rechargeable batteries, and was still willing even after she priced them in Dcell sizes. I reminded her of our past experiments in using rechargeables, and after a short time spent in introspection, she "ok'd" my requests for a spending spree at www.alliedelec.com


A project box, an AC power cord socket(panel mount), two TDK-Lambda 25W 3.3V 6A switching power supplies, assorted colors of hook up wire, and a few screws, nuts and washers, and crimp on terminals for the output strip connectors.

Some old skool cable lacing, mostly just because.

setting power supply to the new output voltage of 3.0 volts(adj from 2.8 to 3.6)

3 pin mini-DIN male and female, selected for low profile of female panel mount solder pins. The switch was difficult to select, since all of them touched the batterys below, or were to large for the DIN plug to fit beside it. Finally found one with suitably small closed brass lugs. (DPDT on-on)

and finally a photo of the entire robot arm which the supply will power.
And the whole project came in under $40, thanks to some found parts in the old junk pile. (connectors and wire etc.) That just about matches what we've paid for the young ones batteries so far.

Any suggestions or comments most welcome,
Kermit

 

[Bernd]

As I was reading the first few sentences I was going to say build a power supply to plug into the robot arm. But I see you did that.

Great minds think alike. Rof}

Nice job on the wiring. Not many people know how to cable up wires like that. Very neat.

Regards,
Bernd

 

[Tin Falcon]

cool stuff . the thing runs on D batteries and you needed two poersupplies??? maybe that is why it was sucking them down so fast. HMM.
I am getting to know and like allied we use them some at work. We have a part time guy that used to use them a lot and he hooked us up. I just piggy backed some stuff on a business order. I just have to cover the cost of any parts I order . It it is heavy I will kick in for my share of shipping of course. I just picked up 10 each micro switches and 10 each hall effect ICs. for CNC stuff. MOre ifo on that arm if you please.
kermit

 

[bearcar1]

Oh, you're not kidding about lacing cables and loose wires Kermit. It is a 'black art' type of thing that unless one has been exposed to it as a phone guy or in the military of 'old', it is virtually unheard of. Plastic ty-wraps (I call them "panties" :big have replaced this obscure type of bundling. Well done, and you used the correct form to lock stitch it all in place. Now your son is liable to lose interest in the arm and move on to other more 'interesting' things....yeah, you know.......... girls! Rof}



BC1
Jim

 

[rake60]

Nice work Kermit!
I haven't seen wire lacing since 1978.
That was the year I graduated from a Vo-Tech school
with a certification in electronics. Cool memories!

Rick

 

[Kermit]

Robot arm from Jameco - clickety click here

The need for two supplies is from the way they used the batteries. The have a center tap on them and have that labeled as a 'ground'. This is hooked up to all the motors. This leaves two ends on the battery stack. One is -3 measured to ground, the other is +3. Therefore I had to use two supplies hooked up the same way. I tied the negative DC line of one supply to the positive DC line of the other, and hooked that twin lead up to the robot 'ground'. Referenced to that point my supplies give me a positive or negative 3 volts. The twin output 'ground' is left constantly hooked up. I hard wired it. The positive and negative leads(as referenced to the ground) are what I have hooked to the switch. Dcells on one end, power supplies on the other, and the robot arm on the center poles. Switch 'on' and the batteries work and the power supply is disconnected. Throw it 'off' and it disconnects the battery and hooks up to the power supply leads.

I still have the 6 volt supply I bought before looking more closely at the wiring of the damn thing. ;D

Kermit

 

[4156df]

Back in my Collins Radio days (late 60's) we used lacing tape with individual ties. As I recall they were tied with a special knot and referred to as "Collins Ties". Lots of specific quality rules regarding placement, spacing and tightness. Thanks for the memories...
Dennis

 

[Tin Falcon]

when I worked at the air base the electrical shop had a braiding machine for making wire harnesses. Tool though.
Thanks for the link I may have seen that in Jameco and forgotten about it.
Tin

 

[Kermit]

I got sent to a special training program once upon a decade or two ago...Cable lacing came up, and I was the only one in the class who had done it before. The single strand lacing I used above was a rarity in the phone offices, except inside individual racked equipment. So, being a good intelligent student, just not very bright about somethings, I proudly displayed my knowledge for the other students. For my reward I was put to work 'sewing in' the bundles of cable the others pretended to be struggling with, as they continued to have problems and generally just got nothing done(yet still got paid just the same as me). Yep, I wasn't very bright back then.

On the upside- I earn a whole hell of lot more now than they do. ;D

Kermit