I just read through the Stingray documentation, and it looks very detailed and complete. I did notice one error - on page 17 the layout of the control board has items 16 and 17 labels swapped. I doubt this would cause anyone confusion, though.
Some tests would be nice to demonstrate what capabilities to expect. I know that Parallax must carefully choose what projects to work on, so take this as a consideration. All the tests should be done with a Nimh or Lipo battery of about ~7.5v and ~3000 mAh. A partial wish list of tests:
-Maximum speed
-Maximum acceleration
-Maximum range
-Maximum slope going up
-Minimum slope going down
-Maximum spin rate
-Maximum weight (with reasonable wear)
-Maximum pulling force
-Maximum negative acceleration (stopping)
-UV resistance
-Maximum ground "shagginess"
I know most of these tests are affected by the user setup and floor material and a million other factors, but it would give an idea of what to expect.
BTW, very nice robot!
Edit: a side note, but I noticed that in the "Pings on a Stingray" source code that the MIT licence was in a CON section, instead of a DAT section. Is this a new unofficial standard?
John Abshier said...
Once the Stingray is assebled, how do you change the batteries?
I guess it depends on how fat your fingers, hands and arms are... As OBC says. He adds another reset button to his Protoboards. I am similarly fat fingered.
But you should be able to remove one of the Sensor Mount Plates and change·them easily. Also if you use rechargables (which·are recommended), you might make a recharging adapter that could plug into the battery wire connectror.
I did not see anything in the documentation that addressed this issue (though I've only quickly looked through it).
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
I'm actually quite interesting in buying a string ray robot. It has a very good body and setup. However, some things I wonder about include...
The batteries (6 AA???) - How long is that gonna last. Like 10 min? What are the test results Parallax has on battery life? If I purchase this robot I need it to last for while running arround.
I ask this because the voltage will fall over time from motor use and from the prop board. So ar arround 5 volts won't the system fail? Or can it dip down to arround 4 before the LDO regulars fail? This is a major concern. Since the batteries are feeding the logic and motors at once.
Also, is there any easy way that an encoder could be used on this? I can buy external hardware but it would be nice to know if Parallax has any suggestions for doing this. I hope this was considered in the design for future upgrades.
The battery pack would dead-dead by the time it reached 5.5 to 6.0 volts. With NiMH rechargeables I wouldn't repeatedly run them below 1v per cell under load. With NiMH the voltage is going to drop to about 7.2-6.9V pretty quickly and then linger there for most of the battery life and then it falls like a rock towards 6v right at the end. You'd want some kind of lockout to shut it all down and keep it off once you hit 5.5v or maybe 5.9V for rechargeables it you intend to run it till exhaustion. I'd do that no matter what actually.
I ran mine for approximately 30 min. on rechargeables.
Dave
Kye said...
This is to Parallax:
I'm actually quite interesting in buying a string ray robot. It has a very good body and setup. However, some things I wonder about include...
The batteries (6 AA???) - How long is that gonna last. Like 10 min? What are the test results Parallax has on battery life? If I purchase this robot I need it to last for while running arround.
I ask this because the voltage will fall over time from motor use and from the prop board. So ar arround 5 volts won't the system fail? Or can it dip down to arround 4 before the LDO regulars fail? This is a major concern. Since the batteries are feeding the logic and motors at once.
Also, is there any easy way that an encoder could be used on this? I can buy external hardware but it would be nice to know if Parallax has any suggestions for doing this. I hope this was considered in the design for future upgrades.
Another suggestion: the Stingray product page should have under related products the ping and ping stand, since IIRC the ping stand is built to fit the Stingray (or vice versa).
Pyrotom said...
I just read through the Stingray documentation, and it looks very detailed and complete. I did notice one error - on page 17 the layout of the control board has items 16 and 17 labels swapped. I doubt this would cause anyone confusion, though.
Thanks Pyrotom!·The picture is correct but the line items are swapped in the list underneath. It's correct in the detailed descriptions in the sections that follow.··I've fixed it for the next revision -- the possibilities are endless·here so I'm sure we are going to be adding more material as time goes on.
Shoot, Whit - I just got finished putting my Stingray together (yes, it came today - Thanks, Parallax!!), and already you're tempting me to start spending money I don't have on it! Seriously - this looks like it would be a good battery pack for the stingray. Of course then you need the charger to go with it:
Actually you would want two of the battery packs and the charger. That way you could charge one while the other was powering your Stingray!
As per Dave above - a thirty minute run time is pretty good. You can do a lot of playing and testing in thirty minutes.
Glad you are having fun with your new bot.
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
I use a123 packs in RC planes.
With the appropriate charger, they can be charged in place in 15 min (no need to buy two packs).
Now you can find 2s2p packs with the same form factor as common NiMh car packs (or DIY).
It would be a nice idea to add a power switch and a charge plug with balancing taps (3 wires).
To recommend!
Having fun with my Stingray, but with no sensors on it yet there is not a lot I can do. I have encountered a problem, though. If I load a very short program into the EEPROM all is well. But if I try to put a longer program in, I get an "EEPROM verify error on COM7" message.
I just got my Stingray kit today, great kit and very easy to assemble even in a hotel room on business. I brought a supply of parts and sensors with me so I'll be playing when I'm not working.· Thanks Parallax for another great product.
Pyrotom said...
Having fun with my Stingray, but with no sensors on it yet there is not a lot I can do. I have encountered a problem, though. If I load a very short program into the EEPROM all is well. But if I try to put a longer program in, I get an "EEPROM verify error on COM7" message.
Pyrotom,
Maybe·you should·post a question about this over on the Propeller Forum. I've never encountered this problem, but some of the other Prop folks may have.
Edit - Just found this thread on the Prop Forum - http://forums.parallax.com/showthread.php?p=845454·You may want to contact Parallax's Tech Support. But this still might be a problem someone has encountered and solved.
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
Back from my weekend trip and I am happy to see activity on this thread. Since I have a couple of full weeks ahead of me, I think that I will wait for my cats to give me a Stingray kit for my birthday next month. While waiting I will be watching this thread for ideas. I do like Whit's rc battery idea since I have a bunch of them lying around for use in cars, boats, and the odd robot.
Thanks for the heads up Whit. The count was down to 10 when I told the cats to order early. if they didn't want to be disappointed when they ordered my birthday present. I just hope they don't hide it in the litter box until the big day!
John Abshier said...
Once the Stingray is assebled, how do you change the batteries?
John Abshier
John,
I am able to slip a finger in from either side of the tail wheel mount and pop the batteries in and out. If you don't have long enough fingers the ubiquitous Parallax screwdriver can be used to gently pry them up for swapping.
BTW - Parallax - thanks for the prompt shipping! This is a best Birthday present I've gotten in 42 years!!
Comments
-Maximum speed
-Maximum acceleration
-Maximum range
-Maximum slope going up
-Minimum slope going down
-Maximum spin rate
-Maximum weight (with reasonable wear)
-Maximum pulling force
-Maximum negative acceleration (stopping)
-UV resistance
-Maximum ground "shagginess"
I know most of these tests are affected by the user setup and floor material and a million other factors, but it would give an idea of what to expect.
BTW, very nice robot!
Edit: a side note, but I noticed that in the "Pings on a Stingray" source code that the MIT licence was in a CON section, instead of a DAT section. Is this a new unofficial standard?
Post Edited (SRLM) : 10/1/2009 6:45:06 PM GMT
John Abshier
But you should be able to remove one of the Sensor Mount Plates and change·them easily. Also if you use rechargables (which·are recommended), you might make a recharging adapter that could plug into the battery wire connectror.
I did not see anything in the documentation that addressed this issue (though I've only quickly looked through it).
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
Post Edited (Whit) : 10/2/2009 7:05:28 PM GMT
I'm actually quite interesting in buying a string ray robot. It has a very good body and setup. However, some things I wonder about include...
The batteries (6 AA???) - How long is that gonna last. Like 10 min? What are the test results Parallax has on battery life? If I purchase this robot I need it to last for while running arround.
I ask this because the voltage will fall over time from motor use and from the prop board. So ar arround 5 volts won't the system fail? Or can it dip down to arround 4 before the LDO regulars fail? This is a major concern. Since the batteries are feeding the logic and motors at once.
Also, is there any easy way that an encoder could be used on this? I can buy external hardware but it would be nice to know if Parallax has any suggestions for doing this. I hope this was considered in the design for future upgrades.
Thank you,
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Nyamekye,
Dave
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Dave Andreae
Parallax Tech Support·
Dave ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Dave Andreae
Parallax Tech Support·
-Stephanie Lindsay
Editor, Parallax Inc.
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No purchase necessary. See back panel for more details.
Tired of the same old robot brains? not enough processing power? Get the Propeller Robot Module now!!
Wonder how one of those RC Car/Truck batteries would work. Something like this? http://www.onlybatteries.com/showitem.asp?ItemID=14501.55&cat1=12&uid=1010
7.2 Volt 4200 mAh NIMH Battery Pack - Tamiya Plug
Specifications:
Voltage: 7.2V
Capcity: 4200 mAh
Chemistry: NiMH (Nickel Metal Hydride)
Size: 6 x Sub-C Cells
Configuration: 2 x 3 - Flat Stick Pack
Connector: Standard Tamiya
Dimensions and Weight:
Length: 5.35" (135 mm)
Width: 1.81" (45 mm)
Height: 0.91"(25 mm)
Weight: 12.31 oz (349 g)
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
http://www.onlybatteries.com/showitem.asp?ItemID=13215.14&cat1=12&uid=1041
Actually you would want two of the battery packs and the charger. That way you could charge one while the other was powering your Stingray!
As per Dave above - a thirty minute run time is pretty good. You can do a lot of playing and testing in thirty minutes.
Glad you are having fun with your new bot.
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
With the appropriate charger, they can be charged in place in 15 min (no need to buy two packs).
Now you can find 2s2p packs with the same form factor as common NiMh car packs (or DIY).
It would be a nice idea to add a power switch and a charge plug with balancing taps (3 wires).
To recommend!
Curt
Maybe·you should·post a question about this over on the Propeller Forum. I've never encountered this problem, but some of the other Prop folks may have.
Edit - Just found this thread on the Prop Forum - http://forums.parallax.com/showthread.php?p=845454·You may want to contact Parallax's Tech Support. But this still might be a problem someone has encountered and solved.
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
Post Edited (Whit) : 10/5/2009 12:14:11 AM GMT
Ron aka sailman58
I couldn't stand it any longer. The inventory count was down to 22 - so I had to order one. I was going to wait for free shipping!
At least now I can sleep at night...
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
Or not! [noparse];)[/noparse]
Usually when I order a robot I get so excited that I cannot sleep until I get it.
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No purchase necessary. See back panel for more details.
Tired of the same old robot brains? not enough processing power? Get the Propeller Robot Module now!!
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
Ron aka sailmen58
John,
I am able to slip a finger in from either side of the tail wheel mount and pop the batteries in and out. If you don't have long enough fingers the ubiquitous Parallax screwdriver can be used to gently pry them up for swapping.
BTW - Parallax - thanks for the prompt shipping! This is a best Birthday present I've gotten in 42 years!!
Doc
CONGRATULATIONS Parallax! Looks like the Stingray is going to be a winner. Better start making a few more...
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Whit+
"We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths." - Walt Disney
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No purchase necessary. See back panel for more details.
Tired of the same old robot brains? not enough processing power? Get the Propeller Robot Module now!!
Looking at your signature begs the question in my mind: Is the Propeller Robot board backward compatible with Boe Bot? Hmmm....
Doc
ON EDIT: thought it might be worth a shot to put the Stingray board on a Boe-Bot but the BOE is slightly smaller. So that's a no-go.
Post Edited (doggiedoc) : 10/6/2009 12:42:11 AM GMT