DHB-10 Dual H-Bridge vs HB25

ChrisL8

What are the relative benefits and drawbacks of the new DBH-10 versus the HB-25s on the arlo?

Is it just cheaper and easier to source, or does it offer real benefits for Arlobot programming and operating?

I'm not really looking to change, but I am being asked about the new kit and I'd like to know more about the changes.

Chris Savage

Hello,

The DHB-10 firmware will eventually have more features added to it, but for now it has obvious advantages over the HB-25 in terms of overall control. The most obvious is encoder feedback support and the ability to move a specific distance using that feedback. Again with the encoders matching the speed between two motors can be done automatically, whereas with the HB-25 you didn't have that option. The same pulse value on two HB-25s would generally result in the motors going slightly different speeds due to variances in the motors.

Duane Degn

I haven't hooked my DHB-10 to my Arlo hardware yet but I've looked at the DHB-10 firmware and it looks a lot like the Eddie firmware.

In case you're not aware the Eddie firmware has been ported to work with HB-25 controllers. A PAB and a Pair of HB-25 controllers should let you do most of the things the DHB-10 can do.

I hope to make some time to compare (in greater detail) the Eddie firmware with the DHB-10 firmware. I'm hoping any control improvements made in the DHB-10 firmware can be added to the Eddie firmware.

ChrisL8

So it is not just a "motor controller" where we send pulse values to cause movement, it is actually a microcontroller that we send commands to and it will "do the right thing" to perform the requested action?
Is that right?

I presume this means a lot of processing load and code is no longer necessary on the controlling board, is that right?

Is it still possible to obtain accurate "tick counts" from the DHB-10 like we could when the encoders were connected directly to the Activity Board?

I admit the idea sounds great. I've always felt like the "ArloDrive" library ported from the "ActivityDrive" library that I use with my AB could use a lot of improvement. If nothing else, it only reads half of the encoder resolution, and while I'm not sure if improving that is important, it seems like it would help with smoothness and accuracy.

Duane Degn

ChrisL8 wrote: »

So it is not just a "motor controller" where we send pulse values to cause movement, it is actually a microcontroller that we send commands to and it will "do the right thing" to perform the requested action?
Is that right?

Correct.

ChrisL8 wrote: »

I presume this means a lot of processing load and code is no longer necessary on the controlling board, is that right?

Right again.

ChrisL8 wrote: »

Is it still possible to obtain accurate "tick counts" from the DHB-10 like we could when the encoders were connected directly to the Activity Board?

Yes, you can request the encoder counts from the controller. This count will be from both channels of the two encoders.

ChrisL8 wrote: »

I admit the idea sounds great. I've always felt like the "ArloDrive" library ported from the "ActivityDrive" library that I use with my AB could use a lot of improvement. If nothing else, it only reads half of the encoder resolution, and while I'm not sure if improving that is important, it seems like it would help with smoothness and accuracy.

I also thought it was a shame to only use one of the two channels per encoder. A full quadrature encoder offers more advantages than just double the resolution. By monitoring the two channels the firmware can tell the difference between a wheel which is actually turning and a wheel which is oscillating back and forth.