Stingray question: How much does it weigh

tomega3

New member here, I am thinking of getting a Stingray.
Anybody know how much it ways with the motors and wheels that come in the kit?

Thanks

erco

I make 47 ounces stripped down, but I used slightly different motors. Pretty close, call it three pounds of fun. No batteries, boards or sensors.

tomega3

Thanks for the info.
So it weighs about 3 pounds just with motors and wheels, no boards or sensors.
I was hoping it was a lot less. Less weight, longer run time I am thinking.

I was planning to purchase one and use the following motor from Pololu
100:1 Metal Gearmotor 37Dx57L mm with 64 CPR Encoder
Pololu item #: 1446
http://www.pololu.com/catalog/product/1446

for slow to medium speed with good torque.

Any idea how long the parallax Li-ion Power Pack-Charger will run a stringray with its stock motors and a couple of boards and sensors?

I read on the forum that someone was looking into 100:1 gear motors with encoders for the stingray, did they every come up with one?
I would rather purchase a tested setup from parallax if possible.

If you know of something similar to the The Li-ion Power Pack-Charger that has 5000 maH or more please let me know
.
I plan to use this motor controller board for my stingray setup
see http://web4robot.com/RoboticBoard.html
3.5 Amps 8-40v

Really appreciate any and all info, I have been looking for a robot chassis for a while and think the stingray is just the chassis I want to invest in rather than something like the Sparkfun Magician chassis and motor setup.

Thanks

erco

Nice motor, that 100:1 ratio will be more useful than the stock 30:1 motors. That encoder must be 64 counts per motor revolution.

I'm partially through making 64 CPR wheel encoders for my Stingray. One of my many simultaneous projects crawling along.

Not sure about battery life, many variables. How much motion, how fast. Note that's a 12V motor you're spec'ing, orig motors are ~7.2V. My motors are Ebay China, also 12V. I plan to use 3x 18650 Li-Ion cells. http://www.youtube.com/watch?v=cAbjISH5WS4

tomega3

Hi erco, nice video, I checked ebay for the motor and found this:
http://www.ebay.com/itm/DC-Gear-Motor-12V-70rpm-37mm-High-Torque-8kg-cm-Micro-DC-Gear-Box-Motor-/150990875645?pt=LH_DefaultDomain_0&hash=item2327c1ebfd

Is this the one you have? If I read the ebay specs right, it indicates a 5.5mm shaft diameter

I also found theis ebay motor, it says 120 rpm 12v with 4,, shaft diameter
http://www.ebay.com/itm/Electrical-Machine-Shaft-High-Torque-120RPM-DC12V-Geared-Motor-for-Auto-Shutter-/330793861086?pt=LH_DefaultDomain_0&hash=item4d04d9bfde

I am just about completly sold on purchasing a stingray. What charger and battery pack do you use?

I see you said 3x Lion cells. I was wondering if a 5000maH LiPo 2 cell or 3 cell rc battery pack and one of the RC chargers would work. I checked into TRAXXAS for rc batteries and chargers, I think a Dynamite Passport Ultra AC/DC LiPo Charger / Cycler may do the trick
see http://compare.ebay.com/like/280655988351?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar

Thanks for your advice

erco

Yes, that looks just like the motors I got, same seller too. Bolts up fine. Not sure about the second motor, looks very different.

A 3-cell Lipo should work fine for 12V use. I have a big supply of cheap 18650 cells and seperate chargers, so I'm planning to use those. http://forums.parallax.com/showthread.php/145503-1.50-Li-Ion-18650-Batteries

tomega3

Hi erco,
have you run your stingray with those ebay motors? If yes, how did they perform.
Thanks

erco

Just quickie floor tests with alligator clips. No processor/encoders yet. Plenty of top end speed for indoor use. I'm going to use one of the cheapie Ebay speed controls and a Picaxe controller. Gasp!

http://www.ebay.com/itm/L298N-DC-Stepper-Motor-Dual-H-Bridge-Drive-Controller-Board-Module-for-Arduino-/130906221621?pt=LH_DefaultDomain_0&hash=item1e7a9e6c35#ht_4818wt_917