Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: Warhawk87 on July 18, 2010, 02:04:49 PM
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Hey everyone!
I decided not to build an H Bridge to control the motors on my robot so now I am looking for motor controlers.... One problem though... I dont know a single thing about them....
I am using this microcontroller: http://www.sparkfun.com/commerce/product_info.php?products_id=666 (http://www.sparkfun.com/commerce/product_info.php?products_id=666)
And two of these batteries: http://www.all-battery.com/12v2600mahnimhbatterypack11620.aspx (http://www.all-battery.com/12v2600mahnimhbatterypack11620.aspx)
And two of these motors: http://www.pololu.com/catalog/product/1102 (http://www.pololu.com/catalog/product/1102)
So what kind of motor controller would be best to run with these components?
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One of the first specs I look at is the Motor Stall Current and then look for motor controllers that can handle the stall current. At least the controller won't go up in smoke if the motor stalls. And of course the controller needs to also handle the applied voltage.
Second, do you need to control 1 or 2 motors? Pick a controller with this in mind.
Third, is the processor interface and what the processor needs to do the control the motors.
There are actually motor Drivers and motor Controllers. The former just provides the switching of the power to the motors and requires the processor to do a lot of work including provide the PWM pulses to set the motor speed (aka L293). The latter has a processor built in and the BOT processor only needs to send a direction and speed parameter. How much code do you wish to write to control the motors?
Pololu and Sparkfun have a few drivers and controllers. The Arduino is a very capable processor board with a good number of IO pins and a large support base in robotics.
Did you look at this page:
http://www.pololu.com/catalog/category/9 (http://www.pololu.com/catalog/category/9)
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Thanks a lot! Your post was very helpful!
Since this is my first robot I think I am going to go with the controller since it seems to be easier... Thanks again!
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And two of these motors: http://www.pololu.com/catalog/product/1102 (http://www.pololu.com/catalog/product/1102)
So what kind of motor controller would be best to run with these components?
12V 5A stall? If you need bidirectional operation and possibly speed control (though ATMega328 you are using has hardware PWM anyway), this is going to be tough to drive with a single cheap IC (the common options - FAN8082, TA7291P, BA6956AN, BA6287F and TA7267BP - are all rated lower). There are several 5A+ full H-bridge drivers, e.g. TLE5206, but they are not exactly cheap ($7+).
You might be better with two pairs of discrete, complementary power MOSFETs (e.g., NTD2955 + NTD4858N) to be honest...
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Hi,
So what kind of motor controller would be best to run with these components?
If you won't be changing direction more than once every one or two seconds, you miught wanna consider this (http://That.Homepage.dk/PDF/PWM+Relay_4_Motor_Ctrl.pdf).
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12V 5A stall? If you need bidirectional operation and possibly speed control (though ATMega328 you are using has hardware PWM anyway), this is going to be tough to drive with a single cheap IC (the common options - FAN8082, TA7291P, BA6956AN, BA6287F and TA7267BP - are all rated lower). There are several 5A+ full H-bridge drivers, e.g. TLE5206, but they are not exactly cheap ($7+).
You might be better with two pairs of discrete, complementary power MOSFETs (e.g., NTD2955 + NTD4858N) to be honest...
I dont know what those are but ill look into it and see what i can learn... Are they just drivers or controllers? Or neither?
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Hi,
So what kind of motor controller would be best to run with these components?
If you won't be changing direction more than once every one or two seconds, you miught wanna consider this (http://That.Homepage.dk/PDF/PWM+Relay_4_Motor_Ctrl.pdf).
Soeren
That link didn't work for me.
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works for me, try right click, save target as. its a direct link to pdf
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The link works for me but it doesnt really help me much... what is it?
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That links doesn't work for me either.
Pretty much every link or picture that Soeren has posted in the past few weeks won't come through. Tried it from work as well, no dice. been meaning to send him a message.
Soeren, i think that domain is blocked by some ISPs here in the states, or there's a broken router in-between.
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The linked works for me in Philadelphia USA.
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Hi,
Pretty much every link or picture that Soeren has posted in the past few weeks won't come through. Tried it from work as well, no dice. been meaning to send him a message.
Soeren, i think that domain is blocked by some ISPs here in the states, or there's a broken router in-between.
That might be, but I wouldn't have a chance finding out where - you (and whoever experience this problem) could perhaps do a traceroute to see where it breaks, but anyway, my only means would be to move the files to a different domain and for the last 1½ year+, I have messed up a wee bit on my domains and servers - a brush with the final going offline (I'm still in medication) really changes your priorities.
Wonder if it could have anything to do with using about 5 times the size allowed by my ISP, but then it would break for all I assume.
Oh well, must get my web sites sorted out (and reacquire my domain names), but it won't happen for a while I'm afraid.
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do a traceroute
Tracing route to that.homepage.dk [212.242.42.163]
over a maximum of 30 hops:
[68.86.181.161]
4 13 ms 13 ms 24 ms te-9-2-ur01.panamacity.fl.pancity.comcast.net [6
8.86.181.45]
5 27 ms 20 ms 19 ms te-3-1-ar01.l3-mobile.al.northglf.comcast.net [6
8.86.181.17]
6 31 ms 35 ms 30 ms te-1-4-0-6-cr01.dallas.tx.ibone.comcast.net [68.
86.91.61]
7 29 ms 39 ms 33 ms pos-0-3-0-0-pe01.1950stemmons.tx.ibone.comcast.n
et [68.86.86.154]
8 37 ms 225 ms 216 ms as174-pe01.1950stemmons.tx.ibone.comcast.net [75
.149.230.150]
9 212 ms 230 ms 227 ms te9-1.mpd01.dfw01.atlas.cogentco.com [66.28.4.17
3]
10 42 ms 52 ms 51 ms te0-2-0-1.mpd21.mci01.atlas.cogentco.com [154.54
.5.218]
11 64 ms 80 ms 73 ms te0-2-0-3.mpd21.ord01.atlas.cogentco.com [154.54
.30.106]
12 85 ms 86 ms 94 ms te0-1-0-6.ccr21.ymq02.atlas.cogentco.com [38.20.
46.10]
13 179 ms 157 ms 160 ms te0-3-0-6.mpd22.ams03.atlas.cogentco.com [154.54
.6.142]
14 226 ms 163 ms 166 ms te1-2.mpd01.ams04.atlas.cogentco.com [154.54.36.
134]
15 178 ms 162 ms 164 ms telenor.ams04.atlas.cogentco.com [130.117.14.238
]
16 167 ms 198 ms 191 ms ti3004c310-ae2-0.ti.telenor.net [146.172.105.53]
17 166 ms 165 ms 184 ms ti3004b300-ae0-0.ti.telenor.net [146.172.105.42]
18 171 ms 172 ms 195 ms 148.122.9.26
19 183 ms 168 ms 169 ms ae0-0.mcr1-albx.ip.cybercity.dk [212.242.6.169]
20 175 ms 165 ms 176 ms geth0-2.er1-oers.ip.cybercity.dk [212.242.6.106]
21 172 ms 168 ms 180 ms dc0.fnord6-oers.ip.cybercity.dk [212.242.4.201]
22 191 ms 169 ms 177 ms uf5.cybercity.dk [212.242.42.163]
so technically the trace route connected? but still won't serve anything to me. That's an awful lot of bouncing.
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um... thread jack? lol
12V 5A stall? If you need bidirectional operation and possibly speed control (though ATMega328 you are using has hardware PWM anyway), this is going to be tough to drive with a single cheap IC (the common options - FAN8082, TA7291P, BA6956AN, BA6287F and TA7267BP - are all rated lower). There are several 5A+ full H-bridge drivers, e.g. TLE5206, but they are not exactly cheap ($7+).
You might be better with two pairs of discrete, complementary power MOSFETs (e.g., NTD2955 + NTD4858N) to be honest...
I dont know what those are but ill look into it and see what i can learn... Are they just drivers or controllers? Or neither?
My question remains unanswered and my problem unsolved. Im trying to look these things up but im just getting a bunch of nonsense I dont understand...
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How much do motor controllers normally go for? because I see a large variety of prices and I dont want to be ripped off
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Anywhere from $20-60
If you want an easy to use Motor Controller, look at spending $60 plus.
I like this one. http://www.dimensionengineering.com/Sabertooth2X5.htm (http://www.dimensionengineering.com/Sabertooth2X5.htm)
If you want a motor driver, $50 http://www.pololu.com/catalog/product/707 (http://www.pololu.com/catalog/product/707)
It turns out i am using the same motors you linked, with the motor driver I just linked. Works well.
I bought the encoded version of that motor, and I just designed an Arduino board that mates directly with the driver board, and turns it into what i call a 'Motion Controller', using feedback from the motors to maintain a certain speed and report back distance traveled. I'll have a few extra boards when the come from the fab factory if you want one.
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Im not sure if im willing to spend $60 on a component like this... would it really be too hard to build an H-Bridge to run this?
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Im not sure if im willing to spend $60 on a component like this... would it really be too hard to build an H-Bridge to run this?
No; I mentioned NTD2955 + NTD4858N earlier in the thread as possible low-cost MOSFETs to do this. The circuit would be essentially this:
http://www.roko.ca/articles/hbridge/bridge1.gif (http://www.roko.ca/articles/hbridge/bridge1.gif)
There's also an $7 IC that will do this for you (see above); or if you are happy with 4A, UCC27424P is a single chip that goes for under $3.
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The reason i didnt jump on the idea of MOSFETs in the beginning was because i had never heard of them prior to this thread, and i dont know how to use them... But this is a learning experience right? So why not! ;D
Are there any drawbacks from using a simple homemade h bridge vs a motor controller?
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Are there any drawbacks from using a simple homemade h bridge vs a motor controller?
Larger envelope, easier to mess up ;-) Otherwise, nope.
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I am a newbie to robots too, still working on my first robot, but I do have some experience with electronics. If you can buy it ready made, do. Its not the construction that is the problem, it is working out why your circuit does not work when everything looks fine, and you do not want to be spending a fortune and many hours with oscilloscopes etc.
I have a http://www.lynxmotion.com/p-577-tri-track-chassis-kit-no-electronics.aspx (http://www.lynxmotion.com/p-577-tri-track-chassis-kit-no-electronics.aspx) and I used a http://www.dimensionengineering.com/Sabertooth2X10.htm (http://www.dimensionengineering.com/Sabertooth2X10.htm) motor controller. I found it easy to test using analogue inputs first from a couple of potentiometers before connecting to a simple serial connection from my Axon2. The user guide is comprehensive and easy to follow.
Good luck
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If you just want it to work then buy a motor driver or controller chip/board.
If you want to learn how to use MOSFET/BiPolars in a demanding circuit then build your own H-bridge. Many years ago I did do this and learned the many subtleties of a real working H-bridge. Now I buy integrated H-Bridge driver chips as the minimum and would buy controller boards if the requirement came up.
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Hey guys,
The TLE5206 sounds like it should be ok for my purposes, but after googling it i just got a bunch of datasheets and pdfs.... Any suggestions on where to buy?
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I'd say digi-key but i just checked and they are not in stock.
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Check on octopart.com
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The links from octopart led to a website where they are out of stock... How do you guys even find out about these things when they are so hard to find???
Any other suggestions on where to buy or a search engine that will lead me to a place where I can buy are apreciated!
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Any other suggestions on where to buy or a search engine that will lead me to a place where I can buy are apreciated!
Looks like this one is hard to find; have a look at UCC27424P instead, maybe? Cheaper, too.
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Any other suggestions on where to buy or a search engine that will lead me to a place where I can buy are apreciated!
Looks like this one is hard to find; have a look at UCC27424P instead, maybe? Cheaper, too.
Actually, DigiKey has several hundred TLE52052 chips ins tock. It's pretty close it would seem.
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will do, thanks a lot!
How do you know all these products? I'd like to be able to know about them and not have to ask everytime i need something!
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How do you know all these products? I'd like to be able to know about them and not have to ask everytime i need something!
Mouser, Digikey, Newark, etc, all have ICs sorted by categories, and support parametric search (e.g. by current, package type). It's a pretty good way to browse.
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The UCC27424P is only rated for 4 amps... Does that mean if my motor stalls the circuit goes poof?
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Check the data sheet. Many of the H-bridge driver/controller chip have either built-in over current protection or a external current sense resistors that will shut-down the output drivers.
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http://octopart.com/ucc27424p-texas+instruments-455107 (http://octopart.com/ucc27424p-texas+instruments-455107)
I dont see anything about a current protection device and I just had a thought, can I run two motors in both directions with only 1 of these? And I dont have a single idea how to work one of these 0.o
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I was just looking at the diagrams for the TLE 5206-2G and I wanted to know if i had this straight....
The motor is connected from the bridge at OUT1 and OUT2 and you have two logic voltages going into IN1 and IN2.... Activating one of the INs causes the motor to go one way, activating the other makes it reverse, and activating both makes it brake? And if thats right then I can only control one motor with this correct?
I'm going to take a look at the other now and see what I can find out...
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I was just looking at the diagrams for the TLE 5206-2G and I wanted to know if i had this straight....
The motor is connected from the bridge at OUT1 and OUT2 and you have two logic voltages going into IN1 and IN2.... Activating one of the INs causes the motor to go one way, activating the other makes it reverse, and activating both makes it brake? And if thats right then I can only control one motor with this correct?
I'm going to take a look at the other now and see what I can find out...
You can drive more than one motor if the total current needed stays within the limits for that IC - but you can't drive them independently. There are some dual motor drivers, but they are usually pretty expensive, it's often cheaper to just go with two separate ICs.
As for ratings - yeah, UCC27424P has an absolute maximum rating of 4.5A. TLE52052 does 6A and is in stock, though.
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So two TLE52052 to control two DC motors? Sounds good! And i assume what i said about how they work is correct?
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So two TLE52052 to control two DC motors? Sounds good! And i assume what i said about how they work is correct?
Yes, except I think they're high impedance when both inputs are high, and braking when both are low. But should be easy.
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What do you mean by high impedance? I dont know what that means :-\
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What do you mean by high impedance? I dont know what that means :-\
You can just consider this an equivalent of disconnecting motor leads.
In the "brake mode", both leads are shorted (by being simultaneously connected to Vcc or GND), which causes the motor to slow down more rapidly and requires more torque to be moved once stopped - it operates exactly the same to a dynamo with an infinite load. In "freewheeling" high-impedance mode, leads are floating, and therefore, the load is removed - and the motor slow downs more gradually and is easier to operate.
[ Note that neither of these modes is really suitable for stopping the motor in place - to do this, you need to first enter brake mode for a very short time, and then reverse direction briefly. ]
All full H-bridge motor drivers support braking, but not all support freewheeling. This one does, which is nice (it potentially allows for more efficient PWM, for example).
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Hi,
[...] if you are happy with 4A, UCC27424P is a single chip that goes for under $3.
UCC27424P is a MOSFET driver (i.e. not a motor controller!) and won't sustain anything like 4A, which is just the peak pulse rating that it will deliver driving a MOSFET past the Miller plateau.
The sustained current is less than 300 mA.
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So two TLE52052 to control two DC motors? Sounds good! And i assume what i said about how they work is correct?
Yes, except I think they're high impedance when both inputs are high, and braking when both are low. But should be easy.
Not quite:
(http://That.Homepage.dk/Img/52052_Truth_Table.png)
Better resolution (http://That.Homepage.dk/Img/52052_Truth_Table.png)
Edit: And the continuous current is 5A, not 6A.
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Just for clarification, High means your applying power and low means your not? Because if they're both low i would like my motors not to move, but both low makes the motor turn clockwise in your table
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Also I'm having trouble finding a place that sells the TLE52052 individually.... Most of them are "minimum of 100" or out of stock
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Also I'm having trouble finding a place that sells the TLE52052 individually.... Most of them are "minimum of 100" or out of stock
Digikey seems to have them as individual parts either as SMD or Through hole
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The truth table for this device (lifted by Soeren from the datasheet in previous reply) shows that it will be difficult to use with PWM without additional circuitry.
ie for clockwise you will need to flick the 2 pins between Low/Low and High/High
and for anticlockwise between Low/High and High/High
But if you aren't interested in speed control - ie you just want full speed fwd, full speed reverse, brake and coast then you are ok.
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Well you cant expect too much from a cheap component right? And digikey says something "timed out" and no its not my account