Banebot Motor Spec Discrepencies

[Karthik]

So here are the motor specs listed on the sheet from Banebots in the KOP as well as the specs listed on the FIRST website

Banebots Sheet: RS-775, Free Speed: 13,000 RPM, Free Current: 1.8A , Stall Torque: 110.8 oz-in, Stall Current: 86.7A
FIRST site: RS-775, Free Speed: 7,300 RPM, Free Current: 1.1A , Stall Torque: 61.1 oz-in, Stall Current: 30A

The Banebots website has specs that match are similar to the sheet, when you take the data into account at 12V.

http://banebots.com/pc/MOTOR-BRUSH/M7-RS775-18

However the FIRST data matches what is shown for the 12V equivalent of this motor.

http://banebots.com/pc/MOTOR-BRUSH/M7-RS775-12

Anyone have any idea on what the actual specs are on these motors? Has anyone tried testing them out yet? The label on our motor is definitely for the M7-RS775-18, but I'm weary of trusting a sticker.

[sanddrag]

I haven't investigated it yet, but can someone scan to PDF and post the green BaneBots page included in the KOP for us to compare?

[banebots]

Please note that the 18V version of the RS-775 was included in the KOP
Part number M7-RS775-18
link: http://banebots.com/M7-RS775-18

The data on our web site is for the motor at 18V, it nominal Voltage
The data on the green sheet is for the motor at 12V, what FIRST will use it at

We opted to donate the more powerful 18V motor because we believed it would be more useful to FIRST teams than the 12V model. The 18V motor will operate fine at 12V with reduced performance as given on the green sheet.

The label on the motor is correct, all FIRST legal motors supplied by BaneBots will have an appropriate orange label to ease inspection and reduce confusion.

Our less powerful 12V RS-775 (M7-RS775-12) IS NOT FIRST LEGAL to the best of our knowledge.

BaneBots

[IndySam]

When will there be info (including availability) of the P80's for the 775 and the new CIM-U-LATOR?

[Karthik]

Please note that the 18V version of the RS-775 was included in the KOP
Part number M7-RS775-18
link: http://banebots.com/M7-RS775-18

The data on our web site is for the motor at 18V, it nominal Voltage
The data on the green sheet is for the motor at 12V, what FIRST will use it at

We opted to donate the more powerful 18V motor because we believed it would be more useful to FIRST teams than the 12V model. The 18V motor will operate fine at 12V with reduced performance as given on the green sheet.

The label on the motor is correct, all FIRST legal motors supplied by BaneBots will have an appropriate orange label to ease inspection and reduce confusion.

Our less powerful 12V RS-775 (M7-RS775-12) IS NOT FIRST LEGAL to the best of our knowledge.

BaneBots

Thanks for the quick and helpful response. Just for your reference, here's the spec sheet from FIRST with the incorrect information.

http://www.usfirst.org/uploadedFiles/Robotics_Programs/FRC/Game_and_Season__Info/2011_Assets/Kit_of_Parts/Motor%20Curves.pdf

[banebots]

P60 with RS775, P80 with RS775 and CIM-U-LATOR should be up on the web site by the end of the week and available for order at the start of next week.

Links to data sheets for the BaneBots motors found in the KOP:

http://banebots.com/docs/M7-RS775-18-AT12V.pdf
http://banebots.com/docs/M5-RS550-12.pdf
http://banebots.com/docs/M5-RS540-12.pdf
http://banebots.com/docs/M3-RS395-12.pdf

Note the RS775 data sheet is for the 18V motor in the KOP at 12V

BaneBots

[kevinhorn]

Thank you, I really appreciate your attention to detail. I made graphs off of the specs on the Banebots site but knew that the 18v data was wrong for this application.
The range of power provided by the Banebots KoP motors gives more "good" options for motoring our mechanisms.

By the way I really like the RS-550-12-Backshaft. This allows us to place a 100 count encoder directly on the motor and would be a great option for next year.

[Tristan Lall]

By the way I really like the RS-550-12-Backshaft. This allows us to place a 100 count encoder directly on the motor and would be a great option for next year.Be sure to check with the Q&A whether that's legal. (After all, it's a different motor with a different shaft, despite the electrical internals presumably being identical.)

[kevinhorn]

Be sure to check with the Q&A whether that's legal. (After all, it's a different motor with a different shaft, despite the electrical internals presumably being identical.)

Tristan,

I was making a suggestion for future years. I wouldnt dream of putting a non KoP motor on a competition bot.:] This is a setup we use on our half size proof of concept bot. The easy encoder mounting made feedback and CAN testing much easier. The encoder resolution is crazy. It would be very nice to have easy encoder mounting available on game play motors. To see some really interesting data on the RS-550-12 connected to a 20:1 P-60 go to http://www.chiefdelphi.com/forums/showthread.php?t=88193

[Paul Copioli]

I just tried to order 12 of the 775 motors on the BB web site and they said they are out of stock. Is BB holding them for the custom gearboxes? When will they be available?

Thanks for the support.

Paul

PS - I personally appreciate the decision to use the 18V version over the 12V version. These will be much better for FRC teams even at 12V.

[banebots]

We had an error on our website that caused some products to incorrectly be shown as out of stock.

All four of the BaneBots KOP motors are in stock and available.

We apologize for any inconvenience

BaneBots

[ttldomination]

Can someone explain their decision for using the 775 over the 550? The specs for the 550 seem to be most similar to the FP motor from previous year. And other than a higher current pull, I don't see much of a reason to use the 775.

Thanks,
Sunny

[Jared Russell]

We had an error on our website that caused some products to incorrectly be shown as out of stock.

All four of the BaneBots KOP motors are in stock and available.

We apologize for any inconvenience

BaneBots

Thanks for the reply. Will the CIM-U-LATOR gearboxes come with our choice of motor already installed? If not, could you outline the procedure for installing them (trying to gauge if it is something we can do at our main shop or would need sponsor help)?

[Chris is me]

Can someone explain their decision for using the 775 over the 550? The specs for the 550 seem to be most similar to the FP motor from previous year. And other than a higher current pull, I don't see much of a reason to use the 775.

I've heard bad things about the RS - 550's durability.

The RS - 775 looks like a powerful motor (check the data sheet) and it is designed for 18 volts, so it has a good safety factor built in.

[Lil' Lavery]

Can someone explain their decision for using the 775 over the 550? The specs for the 550 seem to be most similar to the FP motor from previous year. And other than a higher current pull, I don't see much of a reason to use the 775.

Thanks,
Sunny

The 775 maxes out at ~270W (peak speed), while the 550 is around ~250W. The 775 is also closer in terms of both speed and torque to FRC applications, meaning less reduction will be needed to utilize it effectively. This outweighs the minor differences in current draw, imo.

[Chris is me]

Somewhat related question: Feeding the motor through the 2.7*1 CIM-U-LATOR gearbox gives it a free speed of ~4700 RPM. Is this close enough to the CIM's ~ ~5300 RPM free speed to be useful? I fear that the motor will "fight" the CIMs being 11% slower. Is that a big enough gap that I should be worried?

[Tom Line]

Somewhat related question: Feeding the motor through the 2.7*1 CIM-U-LATOR gearbox gives it a free speed of ~4700 RPM. Is this close enough to the CIM's ~ ~5300 RPM free speed to be useful? I fear that the motor will "fight" the CIMs being 11% slower. Is that a big enough gap that I should be worried?

No, I wouldn't worry. Consider that under load both will be significantly slowed, which means that both will be trying to move your robot or manipulator in the same direction. The only time it really would matter is in the free running state. However, matching them more closely will obviously increase the efficiency of your mechanism.

I've read that comparing free speeds isn't the best way to match motors. Perhaps there is a better way experimentally (put the motor under identical loads and calculate speeds?).

[Tom Line]

Thanks for the reply. Will the CIM-U-LATOR gearboxes come with our choice of motor already installed? If not, could you outline the procedure for installing them (trying to gauge if it is something we can do at our main shop or would need sponsor help)?

Thanks sanddrag. I removed my post here so no one sees it and uses incorrect info.

[sanddrag]

13,000 RPM top speed at 12V

spec sheet courtesy of BaneBots is attached

[Ether]

I've read that comparing free speeds isn't the best way to match motors.

Would you please provide a link to this article.

[Vikesrock]

Does anyone know the reduction of the transmissions on these motors, or did I miss them in one of the previous posts?

This thread is about the Banebots motors which do not have a transmission or gearbox provided in the Kit.