Hi all, I've been working on my first robotics project, and I've learned A LOT. The plan is to build a 4 DOF robotic arm and then eventually put it on a track system and make it mobile. Which is no easy task, trust me I learned the hard way. Anyway I'm using Goteck HC1621S servos for this project, 6 of them to be exact and I'm powering them using a multistar 22,8v battery with a 10000 mAh capacity. The problem is that these servos can do some heavy duty lifting, with a working torque of 23kg, so they require a stupid high voltage and amperage (3-4 amps) I'm using a buck converter to get a steady voltage and amperage output and it's working fine. Where I'm finding a problem (besides the many I've already encountered) is the motion of the servos are extremely laggy. In terms of controls I have tried two things now. I had an arduino hooked up to the signal pins and based the servo position off of the readings of several potentiometers. They code worked, but the servos were very jumpy and after research discovered that the pwm of the arduino is basically nothing. Next I tried a control board/ servo tester which I purchased from sainsmart, and encountered the same problem. Does anyone know any wireless servo controllers that provide a higher PWM and smoother operation? I'm a newbie so I'd appreciate some feedback. I will include a picture and possibly a video in this post Oh P.s I still need to attach the claw to the arm so the physical structure isn't fully completed yet Sincerely, Fredsaidred amateur robotics engineer
Voltage
You are not feeding 22.8V directly to the servos I hope?
You should be using the Arduino servo library.The motion will all come down to your code.
Awaiting the pictures / videos.
Servo library
You can download an Arduino Servo library with a higher resolution, but I doubt that will fix any lag. (PWM is adjustable also on an Arduino, but that shouldn’t be any issue.) The servo you mention uses 6v - 7.4v, Nothing special about that, normal voltage range. Have you checked if your battery and buck converter can deliver the amp draw?
I am not familiar with the
I am not familiar with the Servos you are using. I mostly us the MG996R servos. As far as a control board there are several out on the market. This is the one that I am most familiar with. https://www.robotshop.com/en/veyron-servo-driver-24-channel.html
I have a software package I put together that is a Servo Sequencer that is written in .NET that you can download and use for free. It will currently control up to 8 servos and I am expandingit to do 24. I am also working on incorporating into it the ability to work with the Arduino, Pololu Mico Miestro and SSC-32. Here is a download link for the Servo Sequencer if you decide to go with the Veyron board. https://www.dropbox.com/s/xwbh20edcyml5hr/ServoSequencer.msi?dl=0
If I can be of any help feel free to PM me or just tag me on the Shout Box.
I think there might be a
I think there might be a problem for the battery to deliver that many amps too. You might try a big capacitor in parralel or a better power supply. I had the same problem with smaller servos they where jiggling all over the place. After providing enougth amps they were fine.