Some problems with motor height! Goto page 1, 2Next
Author
Thread
bytraper
Joined: 31 Oct 2005
Posts: 195
Some problems with motor height!
Anybody know of a motor that puts out similar torque/speed as the nichi ra motors but in a lower profile?
The current problem I have is the shell of the bot is 80mm in height and the motor height is about 80mm from top to bottom, and then i need to put a toothed sprocket on it which blows it way out... Need something about 60mm (can have a greater circumfrence) with similar specs? (motor has to be vertical not horizontal)
Any suggestions?
Sun Jan 27, 2008 10:49 am
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Glen and Angus had wide, flat fan motors that might be around 60mm high. They looked a bit like Short EV Warrior motors but I don't know what cars they came out of. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jan 27, 2008 12:56 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
i have some of those insanely flat (30mm) ones from the older plan b but they are a bit fragile, and the ev style motors are probably a bit taller than 70 but are big on power. _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Sun Jan 27, 2008 12:59 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
The pancake fan motors are the flattest U can get, but down on power compared to the nichi ra motor. They are easy to find at PnP too. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jan 27, 2008 1:34 pm
bytraper
Joined: 31 Oct 2005
Posts: 195
Thanks guys, there has to be another solution I just cant find it lol!!
Sun Jan 27, 2008 1:39 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
What size is the weapon? You could do fine with the pancake motor if the weapon is not too heavy or the motor is geared down right. On the other hand, you might think about going to a brushless outrunner motor. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jan 27, 2008 1:46 pm
bytraper
Joined: 31 Oct 2005
Posts: 195
Hey Nick!
Whats new with Jolt? that and rapture are the bots Im a little worried about going up against
Weapon is a 5.4kg ring spinner... out of bisalloy
400mm x80mm x 6mm
The motor is right on the borderline as it is...
Its just going to be too big... I have the wheels at 90mm which is 5mm protrusion each side. but i dont want the gears poking out lol.
These part numbers work at Bursons or Repco _________________ Satisfaction is proportional to effort and results.
Sun Jan 27, 2008 3:50 pm
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
5.4kg is probably too much for a pancake motor.
Plan-B used one, if you can find some old videos you can see its spinup time.
Although they love voltage, you can probably run a pancake at 48v without too much trouble. Perhaps add a fan. _________________ Mechanical engineers build weapons, civil engineers build targets
Sun Jan 27, 2008 3:53 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
I would need some more details to figure out the kinetic energy of the disk, but at 400mm and 5.4 kgs, the Nichi Ra motor is going to get really hot driving the disk - I definitely wouldn't use anything less powerful.
Jolt is waiting for a rebuild and will be back later in the year. I am almost finished with Scissorhands, which is basically Jolt flipped upside down. Between Scissorhands and Rapture, other bots are in for a hard time this year! _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jan 27, 2008 4:05 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Hey Jake, what was the max voltage you ran them at without destroying the pancakes? I never finished my dual magnet version of the pancake motor, but its performance @ 12v was interesting and at +30V it would be excellent for low height bots - perhaps its time for some further testing... _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jan 27, 2008 4:09 pm
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
i think we hit around 30 or so
i believe we were running 24v with a 7 or so v booster on it _________________ Mechanical engineers build weapons, civil engineers build targets
Sun Jan 27, 2008 5:58 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
I am definitely not an electrical engineer, but the trial motor I made with two magnet plates to increase the flux density gave the motor a much lower RPM and increased torque - I think that generally means more efficiency too. Upping the voltage would bring the motor back to a useful RPM at a really handy power output - gear it down a little and it might prove to be a winner for low hight bots. I also worked out a neat & compact way to mount a pulley on the end of the shaft; it places the pulley right down at the motor casing.
Taking that to the extreme, a pancake motor with suitably large brushes and NIB magnets would totally rock! The Thingap motors used the same technology in a small diameter, high RPM design to get 600W - a pancake version would give lower RPM at higher torque and be ideal for bots. Sigh, back to reality... _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jan 27, 2008 6:22 pm
bytraper
Joined: 31 Oct 2005
Posts: 195
Hmmm... modding a motor isnt out of the question... maybe modding a pancake motor could be viable...?
I can always get variable sized brushes from our own brand (spg) motors...
Nick how far away is Sissorhands?
Sun Jan 27, 2008 6:36 pm
Glen Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
not to mention those pancake motors have a horrible tendancy to delaminate the armature if it hits the magnets. even with shaft support i think it would still flex the plate and wreck it. _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum