rogerflies

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I've added a sketch of the upwind side to this post. The sketch of the launch area and the spool is shown on the second reply.

Here's an idea for a new kind of retriever I've been thinking about. I'd like to see what you retriever users think about it.

On the winch side of the field, you would have a 20" diameter spool mounted on a suitable stand to the left of the winch. The spool would consist of two bike rims joined together and mounted on a common shaft and driven by a reversible motor and speed reducer so that it would turn at 100 or so RPM. The shaft would point toward the winch and the line would lead off the spool out across the field alongside the ground line for the winch. The spool shaft is only supported on the left side, the right side of the spool is open.

Standing behind the retriever and looking out across the field, the left side of the spool would hold the "reset" line and the right side would hold the "retrieve" line. These lines would be wound in opposite directions on the spool so that as the line winds onto one side it comes off the other side. The length of the reset line would be twice the distance to the winch turnaround. The retrieve line would only be long enough to go across the field.

To set up the retriever, you would first put a piece of tape on the loose end of the retrieve line to keep it on the spool. The reset line would be passed through a retriever turnaround pulley and then temporarily secured to the retriever base. The retriever would be run in the retrieve direction while the retriever turnaround was walked across the field and staked down to the left of the winch turnaround. A green streamer would be attached to the reset line on the left side of the retriever turnaround.

Back on the winch side of the field, the end of the retrieve line would be connected to a metal ring. Attached to the ring is a red streamer and a lanyard about two feet long with ring on the other end. The "air" line from the winch is passed through this ring before the parachute is attached. The ring at the bottom of the chute is larger than the ring on the lanyard. The parachute would be temporarily secured to the winch base.

The retriever motor would be run in the reset direction to take up about ten feet of line. The reset line would then be stretched as it is pulled back to the retriever, and the retrieve line is attached to the ring which has the red streamer and the end of the lanyard on it. The retriever would be run in the reset direction until the streamers were side by side on the field. Line tension would be adjusted by taking some retrieve line off the open side of the spool, or putting some back on if it is too loose. You would want just a little tension on the line at this point. The tension will increase slightly as the spool turns in either direction.

After setting the line tension, the retriever is run in the reset direction so that the green streamer is at the winch side of the field and the red streamer is at the turnaround. The ring at the end of the lanyard is on the winch line near (but not on) the turnaround. The parachute is on the winch side of the field and we're ready to launch.

The launch is done in the normal manner. When the plane is off the line, the retriever is run in the retrieve direction. The ring at the end on the lanyard moves across the field, pulling the winch air line down right alongside the ground line. When the ring gets to the bottom of the chute, the retriever pulls the chute back to the winch side of the field. Someone holds the chute while the retriever is run in the reset direction until the green streamer is back on the winch side of the field. We're ready to launch again.

So, what do you think?? No more aborted launches from fouled retriever line. No more retriever line drifting in the wind back over the crowd while someone kites their plane up. No drag on the plane from the retriever line. No rigorous training required for the operators. Looks to me like it might work pretty well. Am I missing something??

Soar Head

My Feedback: (5)

I kindof think I have a mental picture. Perhaps a drawing would help.

Questions: (shows my understanding or lack thereof)

Would the plane be spinning the retriever wheel during launch? I think not, but I'm not sure from the description. If so, this is a serious impediment for using lightweight or 2m planes with this system.

Sounds like two retrieve operations are required for each launch. One for retrieve and one for reset. Correct? If so, time between available launches is increased.

Are the retrieve & reset lines tied in a tight loop? If not, the retrieve operation will pull the retrieve line into the air to meet the chute until it gets down. Since the retrieve line is sliding along the winch line, there is a possibility of a big tangle up.

Have you thought about how this would work in higher winds? Or in downwind launches? If during the launch phase the retrieve line never leaves the ground, then this is not an issue.

Is is possible for the retriever line to hang up in the launchline turnaround during launch?

A picture or detailed drawing would be a big help here...

rogerflies

My Feedback: (3)

Questions: (shows my understanding or lack thereof)

"Would the plane be spinning the retriever wheel during launch? I think not, but I'm not sure from the description. If so, this is a serious impediment for using lightweight or 2m planes with this system."
No. The retriever doesn't do anything at all during the launch. The ring at the end of the lanyard rides on the winch line, but wouldn't have much effect. The ring could even be replaced with a small pulley block to reduce the drag even more.

"Sounds like two retrieve operations are required for each launch. One for retrieve and one for reset. Correct? If so, time between available launches is increased."
That's correct. After the launch there is a retrieve step and a reset step. At 100 RPM each would take about a minute. With some experience using the system, it could easily be speeded up some. The faster things go, the more chance for trouble.

"Are the retrieve & reset lines tied in a tight loop? If not, the retrieve operation will pull the retrieve line into the air to meet the chute until it gets down. Since the retrieve line is sliding along the winch line, there is a possibility of a big tangle up."
I think there would be enough tension on the line to keep it pretty close to the ground. Since it works from the turnaround back to the winch, I don't see much chance of a tangle. The lines would just lay down next to each other.

"Have you thought about how this would work in higher winds? Or in downwind launches? If during the launch phase the retrieve line never leaves the ground, then this is not an issue."
The retrieve line never leaves the line. The tension on the line is set when the streamers are at mid-field. Since the side spooling up line is getting bigger than the side paying out line, the tension increases as the streamers move toward the winch or turnaround. Seems like having the lines stay on the ground would be an advantage in high winds.

"Is is possible for the retriever line to hang up in the launchline turnaround during launch?"
The ring around the launch line would be close to the turnaround, but would not be able to get into it.

"A picture or detailed drawing would be a big help here..."
Judging by your questions, you didn't need a picture to get a good idea of the concept. If I get the time, I'll sketch something and post it.

Thanks

rogerflies

My Feedback: (3)

I made up a sketch, but it's too big a file to post. I'll be glad to email it to anyone that's interested.

Micha

My Feedback: (2)

Use two drums on the retrever, side by side.
Pin the one closest to the motor permanently. The other drum, uses a removable pin on the out board end, and with the pin removed, spins on the shaft.
To begin set up all the line on the system starts out on the outboard drum. The loose end is atached to the inboard drum, after its feed though the turn around.
To lay it out, just pull the pin on the out board drum, pick up the turn pully and start walking. Stake out the turn pully, on the motor end wind the outbard end in the opposite direction of the fixed drum and replace the pin.
tada!
now if you can just figure out how to atach the short retrival line at various lenghts and your set.
Just my random thoughts.
Micha

rogerflies

My Feedback: (3)

That's easy enough. Just pass a loop through the ring that has the red streamer and lanyard on it. Make the loop large enough for everything to fit through. Pull it up tight and you have a double half hitch (I think that's what it's called). Won't slip, and it can easily be removed.

The same method can be used to attach the green lanyard on the reset line.

Micha

My Feedback: (2)

You musta been a boy scout.
That is simple enough, Duh'oh.
Do you really need the speed reducer?
I guess if you do, you could mount the drum shaft on pillow blocks,
Them mount the motor under and behind them, use a belt drive ?
Hmmmm,
Micha

rogerflies

My Feedback: (3)

The belt drive would be better. That way the speed could be changed easily by switching pulleys. Good idea.

Here's a photo of a retriever I built several years ago. The aluminum bar between the handle and the pulley would flip out of the way when the motor started. That let the pickup wand swing into position to start the retrieve automatically. Worked well.

Soar Head

My Feedback: (5)

rogerflies,

Sounds like you should build one of your new retrievers and see how it works. You might be surprised how well it works. Or get the opportunity to refine the design.

If you ever choose to sell it commercially, you may encounter some resistance. Just because it is so different from anything else out there.

Best wishes.

rogerflies

My Feedback: (3)

My wife is also full of encouragement for the project. She's even picked out some possible names for it. Since it's experimental, it runs back and forth on the ground, and some of the wheels I was looking at were black anodized aluminum, she suggested I call it the "Black Lab". With a little paint, it could also be the "Golden Retriever". I just hope it doesn't eat airplanes!!

I've started looking for parts and it looks like the project won't cost much more than $100 to try out, since I can do the machine work myself. Finding suitable bike rims shouldn't be much of a problem, but a 12 volt DC reversible motor is a little harder to come by.

Most starter motors are series wound and run in the same direction regardless of how they're hooked up. Might have to do surgery on one of the smaller Chevy motors to make it reversible. It's doable.

If I try it, I'll be sure to post the results. You're right about people being resistant to change, though. I learned that with the Clutch Winch project, the Truly Redundant Footswitch, the Self-Aligning No-Snag Turnarounds, and modifying Chevy motors to use on winches. All turned out to be very workable designs, but not many people seem interested. Since I've thrown them out there with no strings attached, somebody interested in marketing them is free to do so. I'd really like to see that happen.

Cloudbase

Lord knows we need retriever systems for us "more relaxed types"
I set up a system like the pic several years ago at a contest and it made life a whole lot easier than shagging chutes, Austin; and the rounds went much faster. We used a person to retrieve and attach the winch lines at the turnaround pulley, (after the chute had been run down to its own turnaround pulley), then clip them on the return line. With a slip ring as shown, there should be no need for a chute retriever. Ended up needing a couple of batteries for the retriever tho, as it got used exclusively.
Hope this helps..
Ray

rogerflies

My Feedback: (3)

That's a really neat system. I've got a couple questions:

What size and kind of line did you use? Was there a problem with the line wearing from constantly dragging on the ground?

How do you store the line when the system isn't in use? The continuous loop would be easy to set up and run, but spooling up the line at the end of the day would might be difficult. You'd have to cut (or tie) the line to length for various distances to the turnaround.

How much tension did you have on the line? Did it take much to keep the retrieve line from lifting up as it moved across the field?

How long did it take for the retrieve?

Thanks

Cloudbase

Rogerflies
.. we had the envious position of use of a great sod farm, so the only wear and tear was the grass discoloring the line. Used the same 1500 # test braided line as the winches, btw, none of the winches were using nylon line so I can't speak for possible wear on that stuff.
At the wrap up, the winch chutes were fixed to the winch base, then one person at the turnaround end was able to hold the two winch turnaround pulleys, (actually held the stakes) and the retriever pulley stake and with three people gently activating the winches, walk back, keeping tension on the lines for a snug wrap. The retriever line was just allowed to double wrap at the drum and was stored that way, pulley, et al.
We kept the same length of line on the retriever, as the average line on the winches didn't change much for each setup.
Tension..hmm, just enuff to keep it from comming off of the pulley. (clothesline pulleys)
On my system we used two swivel sping clips, (like a dog leash clip), at the turnaround and the other would be at the winch end, so when the retriever dude would clip the two winch lines on and the chutes were returned to the winches, the other clip would be at the turnaround, ready for the the next launch..
Kept the anxious thermal chasers from spazzing out because they missed the lift that the guy ahead of them just got..
I'm sure in retrospect there was some wear on all lines, as they did get dragged back on the grass but the advantage in effort and return time out weighed that problem. Hazzard a guess from memory but I think one minute per retrieve was close to the mark.
I cannot tell a lie, it was several years ago since I use it, (kids growing up and all that other bothersome stuff took me away from my beloved sport, but I'm back!! . Just renewed a lot of old flying buddies still around and am looking forward to pushing the earth out of orbit with the nose of my glider again.
Will definitely be setting up the retriever again, as this old labra-dork retriever has slowed down some.
I hope we can compare success at this in the comming year. Happy to divulge all insider secrets...
Just got my second favourite toy, a digital camera so will post many photos as things progress. Hope you do too.

Best of Luck
Ray

rogerflies

My Feedback: (3)

Here's the new retriever during the trial set up on the field. I've attached the other photos to the next couple replies.

The first two photos show the side-by side retriever wheels, the line guide pulleys, and the reversible gearmotor. The line goes on one wheel as it comes off the other while the retriever is in operation.

The drive mechanism has a quick release that is visible in the center of the wheel. It is is released by pulling it out and turning it 90 degrees. In that position the wheels turn freely while the system is being set up.

rogerflies

My Feedback: (3)

Here's the back side of the retriever showing the gearmotor. It runs at 120 rpm.

You can also see the microswitches that are mounted on the two guide pulleys. The pulleys are mounted on hinges so that if the line goes slack the motor will be shut off.

rogerflies

My Feedback: (3)

Here's the turnaround with the retriever turnaround pulley on the side. The little dowel is a stopper to position the polished ring that slides along the launch line. As the plane is launched, the polished ring rides up on the turnaround and doesn't interfere with the launch line.

rogerflies

My Feedback: (3)

And here's the turnaroud from the other side. It's a little easier to see the polished ring form this angle.

I'm waiting for a good flying day to try it out. More later.