New answers tagged

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The motor spec for L and R and V will definitely e your currents. Holding current: I= V/R. For V=Vavg if PWM modulated. Moving current is reduced by L initially as dI/dt starts 0A at t=0 then rises (exponentially) with a 63% I time constant of T=L/R which tends to be in the 1ms range for small steppers. This means you can use a higher voltage for a period ...


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It's true that it is the LOAD that controls current flow, not the SOURCE Here's an analogy... On your house, there is a water valve that you use with a garden hose right? When you crack it open completely, you get a relatively light stream of water. Dad washes his car with it, maybe mom waters her roses. However, if a fireman opens the hydrant at the ...


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Adafruit/Digikey specifies at DC R=42 Ohms per winding, but since it is a unipolar with a common tap, I believe that is per half winding and only 1 leg of each winding can be powered on so if using 5V across both coils it would be 5V/42ohms x2= 238mA per motor x5 =1.2A But the ULN2003 Darlington has a Vce(sat)= 0.9 V typ. 1.1 V max. @ Ii =250μA and Ic =...


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If each stepper requires 250 mA then your power supply current rating should be ≥ 5 × 0.25 A = 1.25 A in order to run all the motors simultaneously. The combination of motor and driving board will draw the required current and no more.


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Question Which PSU to use for microstepping NEMA17 steppers at 3.2V, 1.2A per phase? Answer (1) Using A4899 and DM542 microsteppers, you can set max phase current, say 1.2A, for your NEMA17. (2) So you can use high volt PSU as high as 36V, 2A, for your NEMA17 at 3.2V 1.2A /phase. References (1) Driving NEMA steppers using microstepper DM542 ... - EESE ...


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Either your stepper motor doesn't deliver enough torque to follow such ramp or the current is too small for this motor. Remedy: increase acc/dec ramp and check the the output current setting of the driver board. $$T=J\alpha$$ The required torque to accelerate the mass of inertia at specified angle acceleration. If the required acceleration is too high, then ...


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The two other answers are technically correct. I want to simply emphasize a singular point they both made. An RPi is a multi threaded, multi core general purpose system on a chip. It's just like your laptop but with less chips. Their GPIO is sluggish. That means they are not best suited to millisecond control applications. You're suggesting professional ...


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Normally I would recommend a "3 Axis Control Board GRBL" instead. But those NEMA34 mean some real business given their 6 A rating. The DM860T correctly provides differential inputs to cope with interferences that are expected at those power levels. If you really need that much steam you could maybe still use the control part from the Control Boards:...


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As such, the raspi doesn’t care about the size of the motor - that is the job of the driver module. However, you will most likely need an interface in order to provide enough voltage and current to the inputs of the motor driver. I’d suggest you consult the forums of linuxcnc as it is likely someone else has done the exact same thing you want to do. ...


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Question How to use MCU (Teens4, STM32, Rpi4B, Rpi Pico) and DM542 microstep driver to control NEMA 17 / NEMA 24 stepper motors? Answer Short Answer There are many possible causes of trouble. I opened the DM542 module coveer and found three optocouplers EL817c and current limiting resistors 270Ω. One cause is on the input side of the DM542. The three ...


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You really don't want to use that type of logic level converter. Fine for I2C, but not much else. Note - these do not invert and only actively pull low. The DM542 datasheet gives you a hint on how to drive it. I'd suggest some BSS138 mosfets would be suitable. Basically 0V to the drain, port pin -> 10 Ohm resistor-> mosfet gate. Source to - of input to ...


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During this delay the Arduino is frozen The solution is don't delay if you need to do something. Only call delay() when you have done all the things that need doing. and only delay the shortest amount you want to wait for the next thing you need to do.


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The delay() function is bad programming practice and it's unfortunate that it is taught to beginners. if(condition1) { // trigger t1 = millis() // start time } if((millis() - t1) > timeDelay1) { // elapsed time // do something } The above code can be expanded to as many timers as you need. The rest ...


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That's a wire harness standard product. Cables are crimped and cut by machines and then are manually inserted in the plastic housings by workers. That's the standard workflow which has the minimum cost for customers. If you need a twisted wire harness than you need to pay more. By the way, a twisted cable will reduce EMI radiations especially for stepper ...


3

I would have to go with a servo motor. Possibly on a worm gear driven rack and pinion. The servo control system, I would include absolute positioning sensors, (opto wheels) so that the motor control optic wheel is fallows the steering wheel optic wheel with precision. I wouldn't recommend a potentiometer as a command potentiometer, because of mechanical ...


2

Your question doesn't make it clear but I am assuming that you want to motorise the steering rather than provide power to drive the vehicle. Stepper Most stepper systems don't have any position feedback. This means that the control system won't know if it has lost position due to a knock or high resistance while driving. On power-up the steering would need ...


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