Hello everyone,
I am looking to identify the motor pictured below. I will also need to figure out how to control the motor. I am pretty illiterate with electronics, but my best guess is a stepper motor.
Any help would be greatly appreciated.
-Jon
I need to be able to control this motor using an existing voltage signal of 1.26-7.15V. When 1.26v is applied the motor needs to move to the open position, and then at 7.15V moves to closed position, while being nearly infinitely adjustable between those two points. Is this reasonably possible?
Hello.
I’ve never seen a motor like that before, but it does not look like a stepper motor or a brushed DC motor, so we almost certainly don’t have a controller that would work for it. It looks like it could be some kind of AC or brushless motor.
- Ryan
I dismantled the motor to clean it and it does not have any brushes. It is all magnetic so I guess it is a stepper motor. I also found out that the controller that is in the housing (not shown in the picture) is run off of a CAN signal. Is there a programmable controller that can put out a CAN signal preferably one that is not powered from USB? Maybe something like the Arduino but one that can send a CAN signal…
I just looked again at the ARM mbed LPC1768. It seems as though this has what I am looking for. It is capable of CAN and it is not necessarily powered by USB. Considering my limited knowledge and information provided, will this unit do what I need?
Hello.
It sounds like you’re asking for reassurances that are impossible to give based on the limited information you have provided. All I can do is confirm that yes, the mbed LPC1768 has a CAN bus, and yes, the mbed can be powered independent of USB. I have no way of verifying that your motor controller really has a CAN interface and, if so, whether you have the ability to control it from an mbed. Also, I do not think that is a stepper motor (it looks like it might be a three-phase brushless motor).
- Ben
I guess you are right, I am looking for reassurance. Interesting that it is such a small 3 phase motor. I am used to 3phase being in big huge machines. This actuator is from a diesel engine so between knowing that and that it I have the diagrams and pin out for the part it says that it is a CAN bus.
This mbed controller has analog inputs, are these 5v inputs? When 5v inputs are used can you exceed the 5v? Say the highest voltage used is 7.15v will anything past 5v just be read as 5v? Or should I implement a voltage divider to bring the votage below 5v?
3-phase brushless DC motors can be pretty small:
flickr.com/photos/microchipt … 497536402/
The mbed’s analog inputs are not 5V-tolerant; you should not exceed 3.3V on these pins. You could use a resistive voltage divider, but note that the datasheet for the LPC1768 suggests a signal with an output impedance under 7.5k.
- Ben
If it is possible to lower the voltage to under 3.3v and impedence under 7.5k will I be jeapordizing anything?
Is there any better suggestion for what I am trying to achieve here?
What is producing your 1.26 - 7.15V voltage signal? If you keep the voltage on the analog input between 0 and 3.3 V, the mbed will be fine.
- Ben
The voltage signal is coming from a Powetrain Control Module of a diesel engine. I understand that these units are not designed for automotive applications however this mostly for a prototype setup and most importantly for race/offroad use.
With the voltage reduction I am concerned about the equivalent of pixelation in an image. That I would lose the smooth operation and I come out with choppy jerky motor movement.
The mbed has a 12-bit ADC, so I don’t expect that to be a problem.
- Ben
My other concern is I was told there are different CAN signals. Is there anyway for me to tell what type that this actuators controller CAN is?
Unfortunately, I am not at all familiar with CAN, so I cannot help you with that question. How did you determine that it has a CAN interface in the first place?
- Ben
I think the bigger problem you should tackle before moving forward with this is trying to figure out the command protocol required to interface with your driver.
- Ben