Ben

[Ben]

Update: Appearently the ESC should be able to take PWM.

[Ben]

Besides the standard ways and kits provided to control this robot,is there any other way like a library or SDK or available API, maybe just access to control robot from other computers available ? Is there anyway to create one ?

[Ben]

Our technicians have checked the tracks and chains of the robot and they are all functioning properly. For some unknown reasons, the track (or motors) on the left moves much slower than the one on the right side. To keep the vehicle moving straight forward, I have to steer it a lot to the right continuously (i.e. applying a turn=’+9′ command).

[Ben]

Then, is there a way to tune or adjust the parameters of the motor mixing running on the HD2 robot? When it is commanded to move straight forward, the left track of my robot moves much slower than its right track (left travels only ~8.72 inches for every 10 inches by the right). This results in a continuous drifting and rotation to the left, and makes it very diffcult to drive along a hallway without hitting the wall every few meters. I was thinking of controlling the individual track’s speed to compensate the difference. Thanks.

[Ben]

Is there a way for the user to control the speed of each individual track of the HD2 robot? I am using the WiFi control package interface program (WiFi ATR 3.4.0 .NET application) to communicate with the robot, and its robot command message contains only one byte for moving forward/reverse and another byte for steering to the left/right. I would like to control the motion of the robot by sending the left and right track speeds (or motor powers) to the robot. Thanks.

[Ben]

Hi Jason

It is the problem that boombaby31 pointed out. I tried to align the screw set and tighten it again. It worked fine for few hours then again I encountered the same problem. Is there a permanent fix or has the screw set worn out?
When I meant “Working properly when switched-off”, I mean that both the coil and the wheels are spinning properly when I physically move it by hand.

[Ben]

Thanks for the reply. But the thing is that the motor work properly when the robot is switched off and I just push the robot manually. The moment I turn it on that’s when it gets stuck. The possible problems I am looking at are the encoders of the motor or the motor controller.

[Ben]

Understood. The problem I had was that I was hooking the negative (black) to the switch along with the positive (red). The switch only needs the positive. Lesson learned.

[Ben]

It was bought as a kit so I had assumed it would be the same way you guys wire them. All I was asking for was pictures to help understand.

[Ben]

Nevermind, it looks like the link above has extra instructions not included in the youtube video portion itself.

Step 3: Mount Sprockets to Motors

The wheels in this robot are chain driven so we will need to mount sprockets to the motor shafts and later to the axles. These are the 14 tooth sprockets with the 12mm bore. Before mounting sprockets, approximate how far out on the shaft the teeth need to be to line up with mating sprocket on the axle. Unscrew set screws and place sprockets on motor shaft. Tighten set screws making sure to tighten the first one to the flat spot on the motor shaft. Use thread lock and make sure set screws are very tight to prevent any backlash.

[Ben]

On step 3 in this video, , it shows installing the sprockets.

In the PDF installation guide, it talks about drilling a 1/8″ hole into the motor shaft.

I don’t see that done in the video. Is it still necessary?

If so:
My I52 motor shafts are round with a flat side. Where should the holes be drilled? There are two set screw holes.

How about the wheel shaft? Do I still need to drill after it the sprocket finds the sweet spot?

Also, the PDF doesn’t detail the location of where the sprocket should be mounted on the wheel shaft.

[Ben]

This is awesome! I’m the Electronics and 3D Printing Instructor at The Columbus Idea Foundry (columbusideafoundry.com) and we just moved into our new space 2 blocks from The Center of Science and Industry (COSI) and I was planning on building an autonomous “tourbot” to go through our facility – for giving remote tours, and as a security droid (like most hackerspaces, we aren’t in the nicest neighborhood). We have fixed security cameras, but with a 23,000 sq ft first floor, we can’t cover all the angles, so a roving security platform is called for. It would also be great for a roving webcasting platform for our meetups (Raspberry Jams, monthly 3D Printing meetups, and other events).

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[Ben]

And what about having discharge rate of about 5A with nimh batteries?

[Ben]

And what about this battery? Is the discharge rate 1A?
http://www.superdroidrobots.com/shop/item.aspx/aa-2600-mahr-nimh-battery/263/

[Author]

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