A group of our students made a robot that had to fit in a 4 cubic foot volume. To maximize the length of the arm they chose to build a frame 1’x4′, long and narrow. Needless to say it did not turn very well (they managed to turn but using the arm to push the robot up!) Here is a white paper I found that explains the physics do the math before you build!
I am enjoying starting to prepare for my robotics course in the fall. I have a reading list prepared that I will use to prepare. Starting with the fun stuff!
Motor curves really help when picking out the right motor for the job. Here is the VEX edr curve.
Lego motor data can be found here:
“Consuming a literary diet built exclusively on the classics does not provide students with the opportunity to investigate their own personal tastes in reading material and narrows their perspective of reading to the school task of hyper-analyzing literature. (Miller, Donalyn p. 124)”
“I have no issue with standardized testing per see; I believe that students who cannot pass the minimum expectations set by these tests are not good readers. What I have grown to mistrust is how the high-stakes nature of these tests has disrupted quality reading instruction (p. 133).”
To prepare for the 2017-2018 season we’ve been chatting about the items we hope to use if we can raise the funds!
Using these on our climber this year we are sold – the versatility allows them to be used in shooters or mechanisms that can support the weight of an entire robot.
item 217-2973 – Quantity: 4 Base VersaPlanetary v2 1:1 with 1/2″ Hex output
Item 217-2816 Quantity: 4 VersaPlanetary Ring Gear Add on kit
Item 217-2817 Quantity: 4 VersaPlanetary 3:1 Gear kit (we can use for shooting)
Item 217-3102 Quantity: 4 – 7:1 gear kit (combine this with the 3:1 to get a 21:1 gear ratio.
Motor 775pro 217-3371 Quantity: 4
Item 217-5046: VersaPlanetary Integrated Encoder Minimu 2
Tubing for conveyor systems
Hollow-Core Round Belting with Smooth Surface, Quick-Connect, 3/16″ OD, Clear
Item 6567K1 – 60′
Connectors – 6567K26 – 2 packages
Round belting as well 59725k731 with 6180k12 connectors
Roller information from Chief Delphi – Tom Line:
I’ll let you in on a little secret I figured out this past year.
Get a polycarbonate roller from mcmaster with 1.125 ID. Put a bearing on one end, and put a versa hub on the other. You see, many common FRC bearings are 1.125 OD, and the versa hub’s “hub” is 1.125. Super glue them in and you’re done. You can either direct drive the versa hub (if you pick a 1/2 bore hub), leave it to run on the plastic with a 3/8 shaft, or bolt a 25 sprocket to the hub if you want to chain drive it.
That’s it. Zero work rollers.
Not very expensive either, and clear so you can put all sorts of gimmicks inside them
Labels for Wiring
Vinyl Tape – simple colour coding for wiring to ensure everything connects in the correct spot.
For shooters etc.
Colson Performa (2.5″ x 1.25″, 1/2″ Hex bore)
Versahubs quantity 8
VersaHub (1/2″ Hex)
#35 Sprocket w/ Hub – 12t – 1/2″ Hex ID
#35 Plate Sprocket – 30t
#35 Roller Chain (10 feet)
Perforated Polycarbonate Sheet (is there a Canadian supplier?)
Gear box for drive train
This past year we tried using a 2 cim drive train – huge difference. Ideally we would love to have a shifting drive train allowing us to switch between speed and pushing power as required. This cost is huge but would be awesome!
30t Gear with 3/8″ Hex Bore (217-3210) quantity 2
Long shifter shaft 2.65 Ratio Spread 217-3291 quantity 2
Pancake Pneumatic Cylinder 3/4″ Bore, 1/2″ travel 217-2778 quantity 2
Vexpro Ball Shifter Pneumatic Fitting Kit 217-2907 quantity 2
CIM Motor 217-2000 quantity 6
Victor SP 217-9090 quantity 6