R2 back together, fine tuning the software

With R2-D2 back together after the extension skin modifications and frame tweaks, its back to the fun stuff...letting R2-D2 meet up with his fans...


My high school classmate Shelby was in town with her family a few days ago.  The look on her son's face, Logan, is priceless!

Later on, my friend Rebecca stopped by with her son Daelyn...(R2 is bigger!)

With R2 back together, it was time to program the ServoCenter card and add support for the new doors in my ArtooSounds program.


Here's a YouTube video of my software in action with the doors all opening as R2 "screams".  I have much more tweaking to do but its a good start!


The ServoCenter card is having a few minor difficulties which I am working with the vendor on.  One issue seems to be power...I seem to be running out with 5 servos plugged into the card.  It supports 16 but since R2 uses multiple servos at one time, I suspect the card will need external power coming in for the card and the servos themselves.  And the card supports all of this.  However before I go crazy soldering, I'm waiting for more info from the tech.


Once the card power issue is sorted out, then I can proceed with adding the computer interface arm to R2.  I have a motor, mounting hub and spot to mount it.  I just need to pickup another Syren 10a motor controller.


That's it for now!
 

More fine tuning and R2 is back together

Putting R2 back together, I had a few checklist items I wanted to eye over closely.

First was the motor power wire that fits in the battery box.  The 10 guage wires needed to be secured closer to the motor.  Putting the battery box on the motors is a squeeze as it is....battling the wires every time was getting very annoying.  Easy fix!

Next up was the battery charger plate.  The LED lighting that came with it sports 30 lights.  I had 23 holes.  So, I added 7 more to use up the remaining lights.

While I had the drill press going, I also put two shallow holes on the sides of the center vents.  The vents keep managing to slide out of position on me so this should help.

With the pieces in place, it was on to the electronics.

One thing I needed to do was fire up the Roboteq Roborun software and change some settings on the AX3500 motor controller.  Plugged into the laptop and powered on, this was a cinch....I merely leveled out the power and upped the acceleration a bit.  Here's the settings prior to changing.

Once the changes are saved to the card, we're all set to go.

I had a few problems with my radio, the mix settings got screwed up.  This allows two channels to work as one.  In the case of the drive motors, I use the aileron and elevator channels.  I found I still had one leg dragging a bit but finally solved that riddle.  Briefly, for some reason the setting got trashed....creating it again, setting one motor for +100% and -100% solved my problem.  

After a few test drives, R2 is working fine.  I am paying close attention to body sway with the extensive frame mods.  Here's R2 all lit up and back together.

 With R2 back together I can resume work on the programming side, adding the new doors/servos to the application I have written.
 

Foot drive adjustments and shock dampening idea

This evening I did some work on the foot drives.

One issue I have had since I got R2 operational has been one side is faster than the other.  So, driving R2 with the remote is similar to driving your car with one of the front tires pulling to the right.  Its manageable but despite trimming on the remote and reducing power to the stronger motor, nothing has really changed.

With the legs off, I inspected the feet and noticed that one of the ball-casters was very worn compared to the other.  I had purchased a spare set last year, so that was an easy fix.

While a dragging omni-ball could slow one side down, I decided to check the belts.  The side that runs stronger had about 1/2 inch of slack.  The slower side was about half that.  So, I decided to loosen the mounting bolts, reduce the tension a smidge and made it even with the other.  Between these two changes, perhaps we'll solve this oddity.

Finally, I came across some rubber grommets at the hardware store recently.  My thought is that placing these on the shoulder bolts, between where the leg attaches to the shoulder, may help reduce some vibration.

With the legs back on, now its on the tuning the electronics and re-connect everything.  Here I am about to plug into the Roboteq AX3500 motor controller card.  The software will allow me to make changes to the card's settings.  In this case, I am going to change the power settings to the motors so they are both equal again.  And, I am going to adjust the acceleration a bit.  I had it tuned way down but need to bring it up a tad to a faster walking pace.

Skins, door panels and servo work completed

Last night I finished up work on R2's front skins.  

The remaining work I had was adding mounts on the frame for servos to bolt into.
Some, like the charging port, required some creativity...

The charging port door was quite a challenge.  The charging plate required extensive trimming for the linkage to fit thru.  And, I needed a larger servo horn to get the proper angle to apply force on the hinge.

Due to time constraints, I have left the door besides the coin slots alone.  I'll put a servo and linkage at a later time.

I did put a servo and linkage on the last remaining tall door.

With that done, it was time to put R2's skins back on and prepare to lug him upstairs.

With R2's structural mods done, I can work towards getting the electronics and servo wires organized.  I also have to install the new Netbook I bought for R2 a few weeks ago.  I have yet to test it inside R2, so that's a biggie.

That's where we are at now!

Hinge replaced, frame mods completed

This afternoon I resumed work on the frame rods I started on previously.  

The only thing I was missing was some shorter screws and a some washers to make up for any shortfalls in my cutting.

It turns out user one washer on each side worked fine.  

It turns out that one hole is bit off from centerline so it looks a bit awry....but will work fine.

Finally, after letting the Goop adhesive dry overnight, I was able to see how the JAG hinge is working out.  As you can see in the photo below, these work great!

I began work on mounting a servo for the new door hinge and charging panel.  Next time I will show you how those are working out.

Added support rods to frame, replaced hinge

Tonight I got to work strengthening the frame by adding two vertical supports under the shoulders.


Once I had measured up the size and location, I just had to remove the shoulder mounts to accommodate the drill.  The frame looked pretty sparse with those removed...

I bought some bar stock aluminum rods from Lowe's.  I bought the threaded type which made my cutting a lot easier.  Since I do not have a miter saw, it was slow work with the hacksaw.

It was a lot of work drilling and tapping the holes in this thick material.


Tomorrow I need to purchase some shorter screws since I was unable to thread much more than a .25 inch into them.  However, here's how the frame looks now with the additional supports in place...

The other outstanding issue I had to deal with was one of the front doors.  This door is the one the computer interface arm comes out of.  The door can not open as wide as it needs to for the device to deploy properly.


The solution was to remove the Robart hinges and replace it with the JAG one, which is designed for the skins and offers the radius needed to open further.


I also decided to retire JB Weld and go with Goop.


Due to the location of the door, I used a large magnet on each side to apply pressure while drying.

I've spent so much time re-doing hinges....if you can jump in on one of Jerry Greene's part runs when he offers these, get them!  Yes, they aren't cheap but they work exceptionally well and made to work for this specific purpose!

Still tweaking!

And I thought these enhancements would only take a week or two, tops!

This evening was fraught with some progress, some uncanny malfunctions and the sort.

First was the charging port door.  Its been hinged for weeks and I was working on how to mount a fullsize servo to actuate it, the JB Weld failed on one of the hinges.  So, that set me back a day fixing that yesterday.  

Today I wanted to size up and see how the hinge would work with a servo.  It turns out the gaps in the charging plate for the hinges were a bit high, so I would need to file those down a bit.  It looked perfect...then I realized the frame rod was right in the way too.  Ugh!

So, with the dremel and a grinding wheel attachment, I marked and gouged two spots in the frame rod to allow the hinge to open and close without being blocked....

As I lined the skins up, it became really obvious that there is no practical way for a servo linkage to fit in all of that.  (Not that being impractical hasn't been tried before!)  So, I decided to call that section "good enough" for now and decided to move on.

One thing I have been meaning to fix was the mounting screws for the skin to the frame.  Short screws keep working themselves out, so I wanted to lengthen the hole and re-tap it.  I carefully started to drill slowly when I heard a pop.  I removed what was left of my drill bit and see that my Craftsman drill bit had failed, snapping off inside the hole.  

Great.

Well, I thought, I can just patch the existing hole in the skin, add some touch up paint and just drill a new hole.  I drilled the new hole then started on the new hole for the other side.  Pop!  My second Craftsman drill bit snapped 10 seconds into the process.  

Amazing.  I've drilled and tapped holes for years with these bits.  For two to fail within 10 minutes of each other....remarkable.   I dug up my new set of DeWalt bits and finished the job with those.

With GREAT caution, I tapped the holes with a 4-40 tap so that a 3/4 inch hex screw would go inside.  That went fine and now R2's front skins have new mounting holes....

I was seriously pondering if I wanted to continue work at this point.  However, I decided to do one more task...cut away spots on panel insert so I can access the center vent set screws.

It wasn't very elegant work but its also not in very noticeable area (til now!).

At this point, I decided to quit while I was ahead!
 

Routing and labelling servo cables

It was time to label and route the servo cables around the frame today.
With five servos in the front skins, it was important to label this mess!

A while back, I bought some wiring labels at Lowe's that seemed perfect for this job.  The long, nylon adhesive with the number all over it worked perfectly.  No change of a paper label ripping loose or magic marker/pen smudging off.

I had drilled out some 3/4 inch holes in the electronics tray so that the servo cables could route around and into the ServoCenter card.  I also used up several 12" and 18" servo extension cables in the process.  

Two issues have cropped up.

First, the charging port door will not close properly.  It needs some more tweaking for the hinge to fit.  I have no idea how I didn't spot this before...I suspect because the skins were only clamped on and not bolted in.


Second is the door below it.  Like the charging port door, its powered by a micro servo.  The servo horn for the micros are very, very small and thin.  I think I am going to have to upgrade each to regular size servos and be creative with the linkages, much like the computer interface arm.  Since the micro servo horn can not hold a pushrod like a normal servo, these will eventually fail in the configuration they are in now.


A minor setback....but I suspected they may not be the right part for the job when I installed them.


Tomorrow I'll extract those micro's out and size up a good place to install the regular servos and linkages.

Installed door enclosure, premeasuring for SoftPot

Today I did some more work on R2.

A few months back, I ordered an aluminum enclosure for one of R2's panels.  This piece was originally intended for my new frame I am using on the second R2 I have under construction.  However, since I had such good luck modifying the charging port to fit in my original R2, I wanted to see if I could make this fit too.

What I like about the enclosure is that when the door is opened, its there....no longer are you staring at R2's guts...batteries, cables, etc.

I drilled and tapped two holes in the frame for the piece to bolted in.  I had to trim the enclosure with a dremel cutting disc so that the servo linkages and hinges could swing open and shut.  I also have to trim  the side that is closest to the vents.  Otherwise I can not access the set screws that secure the vents.

Once I had this done, I wanted to measure the Softspot potentiometer on the top of the frame.  I have a few ideas but also need to plan for installing a slip ring, which allows for an electrical connection to exist between a spinning surface (similar to how the electronics work in your steering wheel).

Tomorrow I need to label all the servo cables then route them around the plastic cord organizers I installed.  

I'm also going to try buying some rubber gasket pieces that will go on each leg bolt...just another effort to dampen some of the vibrations from the legs and feet.

That's it for today!

Door panel servo install, new receiver and vents are back!

More progress to report!

This evening I made a servo bracket and mounted it inside the frame...

After a lot of careful experimentation, I hooked up what seems to be the best location for the servo horn.  Again I have opted to use an aluminum one that is longer than a standard servo horn.  Better leverage and works really well.

With that installed, I moved on to the next task, replacing the receiver.

The Spektrum radio I have is the 6DXi.  The receiver is the BR6000 robot receiver, which features failsafes.  Mine is an early edition and there was a problem with how the radio and receiver talk to each other.  It would take 5-9 minutes for my receiver to light up and "lock on" to the radio's digital signal.  In my research, I found that this is because the receiver is scanning so many channels.  

I had a chance to speak to someone from Spektrum technical support and they suggested moving up to a AR7600 receiver, which supports 7 channels.  This receiver will not only lock onto the transmitter right away, but work with my existing radio.  No need to ditch my 6 channel radio and buy a new one.  I just have one channel I can't use.

Following the instructions, I quickly went thru the binding process and had the new receiver working in under 5 minutes.  Now, no more long wait.  The connection is made right away.

 
The last thing I did this evening was get the center vents re-installed.  

It didn't go very smoothly as it was very slow work.  I had to file down portions of the surround plate before each fit into position.  I have the set screws set and they are clamped into position.

The center surround plate still irks me.  

On one hand, R2-D2 has been thru many space battles and does look a little worse for wear in the movies.  So, a dinged up piece probably fits right in.

And, on another, I would like to have some plastic material laser cut to the dimensions of this piece, paint and replace.  Plastic would be much more forgiving.

So...we'll see!

Here's where I am at now with R2...

 

Repaired center vent surround piece, charging port lights

This evening I dove right in where I left off the night before.

With the epoxy dry from the panel I worked on last night, I was able to proceed on to the center vent surround piece.  This piece got pretty warbled from banging into an elevator door, dinging into the side of the van during a tight turn and so on.  

I tried my best to gently bend it back into shape.  Ideally, I would use a roller to just fix it once and for all but I do not have access to one.  Once I had it as best as I could do, I taped it to the skin.

From the back side, you can see there really isn't much surface space for adhesive.  In the past I have used JB Weld (epoxy) and silicone.  Both worked but not for long.  

I decided to try contact cement.  I'd essentially just paint it on hope it does a better job holding.  I opted to go thick, as you can see...

I let that dry for 3 hours and worked on a servo mount for the front panel.

I also had to tweak the COM-8 Charging port piece a bit...I removed the lower piece of it.  It was easy enough to simply unscrew and remove.  The horizontal piece had to go since it would strike the two micro servos near it.

James from COM-8 includes a strip of battery powered LED lights.  I decided to toy with them and see how I liked the color/pattern.

I need to figure out a way to replace that battery pack with onboard power.

The LEDs simply slide into the metal framework.

I removed them and resumed work aligning the servo motor linkage to the new panel that opens.  

I installed the servo mount and after adjusting a 2-56 sized pushrod to the right size, the only thing I need to do is swap out the servo horn.  My local hobby store has longer, metal ones that will work better than the plastic ones that came with the servo.

Tomorrow's to do list isn't too terrible...align and mount the center vents, using set-screws to lock them into place.  I have to route the servo wires and secure them in place, then I can work on programming the servos to the computer.

Fun stuff...its getting there!
 

Expoxied the hinge and more frame tweaking

Today I resumed work on the front skin panel.

First I lined up the panel in the correct position, used painter's tape to hold it in place, then laid the skin down.  With the hinge clamped into place, I used a pencil to trace around...I will apply epoxy (JB Weld) in that area.

Epoxy applied, I place the hinge gently into position and make sure none of the adhesive oozes into the door sill.  Gently, I clamp everything into place.

JB Weld takes 24 hours to harden, so we are done the skins for tonight!  (Side note...every piece I have applied with JB QWIK has fallen off.  Stick to the good stuff, waiting 24 hours will reward you!)

I took apart the utility arm carrier and drilled and tapped the holes to mount the backplate on with.  While I had that off, I decided to make another modification....the COM-8 charging port that is designed for the newer frames.  For now its just a decoration since the panel door can't really open far enough for it to be seen.  But...this is the time to add it in.  I can tweak the door later.

Here's the back view, with the back plate installed.

Tomorrow I'll inspect how the door works out and make any needed adjustments.  The next big feat will be figuring out where to mount a servo, plus the linkage, for it to open and close.

 

Freed up another sealed up door panel

Once again I have decided to unseal a door panel I had initially decided to seal shut.  

My thinking back when I put the skins together was to simply leave them sealed and closed so they would not flop around.  It was also a lot of work to hinge, servo and modify the frame to accommodate them.

Now, a few years later, I have gained confidence in working with metal, electronics and servos...so, here we are.

Here's the "before" picture of the large panel sealed with JB Weld...

Once the JB Weld is sanding off with the dremel, I used a wire brush attachment to remove the material along the edge.  With a little force, the panel popped right out.

The adhesive I used to bond the skins together, 3M # 77, is a bit brittle.  I glued the panel piece and trim together with superglue.  All that remained was to clean up where the panel was, some minor filing and cleanup with the dremel wire brush bit again.

And that's where I am at tonight.

Tomorrow I'll epoxy the door to the hinge piece to dry overnight.

I will need to move a frame rod to allow for enough space for the hinge to move.

And then...another challenge....finding a location for the servo!

(Actually I think I can mount it to the back of the utility arm back plate...once I finish drilling and tapping the new holes!)

It bums me out to have R2 out of service for so long...I have had a number of requests for R2 at the hospital.  But, so many people made good ideas, I want to implement them!  It just takes some work, time and testing to do it right.

More tomorrow!
 

R2 upgrades continue: Frame, computer interface arm and installing the ServoCenter card

Work continues!

It took a while but I have the computer interface arm working so that it extends and retracts.  I used an aluminum servo bracket screwed into the resin piece, then attached a servo and extra long metal horn.

There was a fair amount of trial and error with the r/c aircraft pushrod, the alignment and so forth.  Here is a YouTube video of the setup in action.


It worked but was a tad slow.  I decided to consult with my friend Warren at King's Mountain R/C in Orrington.  Warren suggested a more powerful servo, so I upgraded from a 72 ounce (torque) model to a 142 ounce model.  

One big difference is that this servo has a metal top ...

While I have the interface arm working, I am going to have to put this mini project aside for now.  The piece is too heavy for the pan/tilt servo system I had hoped to use.  I'll have to refine my ideas some more and try again with a motor tipping the device in and out of the body.


The next thing on the To Do list was shoring up the frame.  I had to remove two frame rods to allow for the tall door to open and another for the two small doors to open/close too.  


What I was able to do was move the frame rod back about an inch.  This stabilizes the load on the frame and is far enough out of the way for the door hinges to open and close without obstruction.

Next up was mounting the ServoCenter USB to Servo controller card.  This card connects to R2's onboard computer via USB and allows my software to communicate directly with the servos.   Once I found a good spot, I wired it into the RigRunner with the proper fusing and tested it out.  

After I took the photo, I added some .75 inch diameter holes below the card.  The servo cables will feed in thru there into the card.   


One of the final things I tackled today was the backplate that goes behind the utility arms.  For the longest time I have simply taped it into place since, well, that worked fine!  I lined up where the plate should bolt into the frame and marked it off....

If you look real close, you see two blue dots on the vertical piece.  Tomorrow I need to dismantle that assembly and make the mounting holes.  A fairly quick drill, tap and bolt into place task.  


What's next?  


*  Repairing and re-mounting the blue surround plate that goes around the center vents.  It got dented a while back and popped loose.


*  Center vents need to be re-aligned and locked into position


*  Install the SoftPot potentiometer.  This device will input data into the ServoCenter card and allow the computer to know where R2's head is pointed.


That's all for this update.