AM Super Shifters

[chris31]

Originally Posted by Mr. Odlies

Back to the weight, that was measured with 2 cim motors on the gear box's. Andy, is there any plan for a 3 speed gear box? Also could you put out a inv file of your mecanum wheels? On your site there is just the right front and rear left.

That is because they are the same thing. All of the CAD is on their website.

[Mr. Odlies]

Well with mecanum wheels, they have to be angled like this:

[Madison]

Originally Posted by Mr. Odlies

Well with mecanum wheels, they have to be angled like this:

The diagonally opposed wheels are the same. You need only the two, mirrored CAD models to model the full drive train.

Also, you'll want to arrange your wheels differently than is shown in that diagram. I'll leave figuring out why as an exercise to the reader.

[waialua359]

the black housing on ours is a little too short in length.
We are actually replacing our housing with spacers to lengthen it just a bit more allowing for the gear to spin more easily and to reduce weight.
We havent figured yet on how we would create an adapter plate to fit the larger FP CIM motor. Too much interference everywhere.

We were able to make a plate for our older AM2 shifters with direct drive shaft at this point for prototyping.

We havent yet tested ours.

To Andy: As we inspected our encoders, we noticed that the shaft does not fully get pressed in there. Is it supposed to be like that?

thanks.

[Andy Baker]

Originally Posted by waialua359

To Andy: As we inspected our encoders, we noticed that the shaft does not fully get pressed in there. Is it supposed to be like that?

The portion of the Wheel Shaft that has the encoder disk pressed onto it could be a bit longer, but there is enough of a press there for the encoder to function properly. The encoder disk is placed on the shaft before shipment at the right location. If the disk is pressed further toward the circuit board, it may not work properly.

Andy B.

[waialua359]

Originally Posted by Andy Baker

The portion of the Wheel Shaft that has the encoder disk pressed onto it could be a bit longer, but there is enough of a press there for the encoder to function properly. The encoder disk is placed on the shaft before shipment at the right location. If the disk is pressed further toward the circuit board, it may not work properly.

Andy B.

mahalo, mahalo, mahalo......
By the way, how was the black housing painted....anodized, powder coat, ??
thanks.

[Cory]

Originally Posted by waialua359

mahalo, mahalo, mahalo......
By the way, how was the black housing painted....anodized, powder coat, ??
thanks.

When I saw it at IRI it was anodized.

[Jim Meyer]

We bought a couple of these and received them incredibly quick. Three or four days IIRC. It would take at least a week for our team to build these ourselves.

They certainly seem to be quite solid. They may be a little on the heavy side but the reliability I expect them to have more than makes up for their heft. We can spend a little effort lightening these and then use all that extra time making the rest of the robot lighter.

[JesseK]

We're pretty excited about our shifters; they came in a couple of weeks before the break and we had the opportunity to run one with just a single 2006 CIM motor and the servo. Our only problem was (still is) mounting it to our prototype frame, but that's because the mounts we made twisted when we welded them to the frame -- we're making a new process tomorrow to avoid this on the actual frame, but other than that we're very impressed with this transmission.

Also of note is that the keyed universal hub is fantastic mate for this transmisssion, and the hubs look like they only need a slight shave for the flat AM sprockets to fit over them -- something to consider if you plan to direct-drive one of your wheels from the transmission.

[Richard Wallace]

Originally Posted by Jim Meyer

We bought a couple of these and received them incredibly quick. Three or four days IIRC. It would take at least a week for our team to build these ourselves.

They certainly seem to be quite solid. They may be a little on the heavy side but the reliability I expect them to have more than makes up for their heft. We can spend a little effort lightening these and then use all that extra time making the rest of the robot lighter.

Ordered a pair Saturday about two hours after the kickoff presentation ended. Received them this morning about 10am.

As Jim says they seem very solid. Shifting is very smooth. And there is clearly some room to reduce weight by simple operations the team can perform.

[waialua359]

Originally Posted by Richard

Ordered a pair Saturday about two hours after the kickoff presentation ended. Received them this morning about 10am.

As Jim says they seem very solid. Shifting is very smooth. And there is clearly some room to reduce weight by simple operations the team can perform.

swap out the black anodized housing with aluminum spacers on the corners. We had to anyway since the black housing was too thin causing our gears to bind.

[Aarnat]

Hi all,
We have two AndyMark super shifters with two motors going into each transmission, and servos that change the gears. We definitely look forward to using them and seeing our robot fly around the track.

My question is: How has your team programmed them? My idea is to have two switches on the joystick: one to switch the transmission into the first gear and the second button to switch it into the second gear.

Also I read on the AndyMarrk website that we should ease off the accelerator when we shift; especcially since we are using the servo shifter. Has anyone had any problems with that?

Thanks!!!

[CardcaptorRLH85]

If you don't ease off of the power when you shift you will hear the most gut wrenching sound of gears at high speed crunching...we haven't managed to break anything since changing gears during autonomous mode wasn't really necessary last year and our driver slowed down when shifting during teleoperated mode.

I've been doing a bit of sensor code testing with our 2007 robot since I can't get any time with the '08 bot yet and I have noticed that after too many high speed shifts the servos tend to not make the gears mesh like they used to. I guess what I'm saying is, don't try your luck with the servos.

For your first question, I'll post the code that we used to make our servos go ^_^ We used a PWM Y cable to connect both servos to a single PWM output.

This part was in our Default Routine function (HIGH is defined as 1 and LOW as 0)

if (p1_sw_top || p2_sw_top) {gear = HIGH;}
if (p1_sw_trig || p2_sw_trig) {gear = LOW;}
Set_Gear(gear);

This is the Set_Gear function (the else is a just in case thing ^_^)

void Set_Gear(char set)
    {
        if (set == LOW)
        {
            pwm05 = 255;
        }
        else if (set == HIGH)
        {
            pwm05 = 0;
        }
        else
        {
            pwm05 = 127;
        }    
    }

This made it so that the top buttons for either the first or second controllers shifted to high and either trigger shifted to low.

[kramarczyk]

Originally Posted by M. Krass

Also, you'll want to arrange your wheels differently than is shown in that diagram. I'll leave figuring out why as an exercise to the reader.

That depends, is the diagram a top view or a bottom?

[Mr. Odlies]

Very true, Andy Mark just came out with a new set of mecanum wheels. What makes them better then the old set?