8059A, J and Z : Singapore Vex Edition (Reveal)

VEX Robotics Competition Discussion VRC > In The Zone (17/18)
#1

With Singapore Vex long over, the time has come around for us again to reveal some of our robots that have taken part in the competition.



We’ll go through 59Z, J and A. 59A and 59J are defense oriented robots (both essentially built in 1 day, with 59A comprising mostly of very busy senior students, and 59J having to work around the very severe change of SG14 in a very short timespan). 8059Z was designed to be a typical offensive robot.

Specifications:
This robot was constructed over the span of three days, drawing heavy inspiration from a prototype (8059D).

Base:
6 motor rear wheel drive (speed gearing), direct drive on 4’’ wheels

Lift:
2 motor ( high torque ) RD4B, geared 1:7
Three-point latex system
Possibly unnecessarily tall? (7 by 7 brackets)
Together with chain bar, has the ability to score 12 cones on stationary and 18 on mobile goal

Cone intake system:
1 motor chain bar, geared 1:3
1 motor claw, geared 1:1
Chain bar swivels either downwards or upwards 90 degrees, reducing total motion of chain bar

Mobile goal intake system:
2 motor linear slide mechanism, geared 1:1 using strength motors
Reliably scores in 20 and 10 point zone (chain bar guards stack for stacks more than 6 cones high)

Autonomous: 9 points, excluding the highest stack bonus (1 mobile goal and 2 cones in 5 point zone)


Programming skills: 32 points

Specifications:

Base:
10 motor 1:1 (speed gearing), direct drive on 4’’ wheels
Denial of zone ability

Arm:
2 motor 1:2 (torque gearing)
Latex assist
Speedy scoring of 10 and 20 point zone ( does not require robot to cross pipe)
Carries mobile goals with stacks of cones

Specifications:

Base:
10 motor 1:1 (speed gearing), direct drive on 4’’ wheels

Mechanism:
Pneumatic Release, 36 " wall ( was dramatically shortened from 67")
Denial of zone ability
Knocks over large areas of cones
Stationary goal pneumatic release blocker

The original 59J was just a bit longer, with a pneumatic brake. The robot was intended to stay mostly stationary, blocking off the zones:

Do feel free to ask any questions. We’ll try our best to help! (Not so sure about those part list requests from last year’s threads, though)

#2

Aww, can I at least get an instruction manual?

#3

Great reveal guys! Love your robots!

#4

8059 does it again!

#5

As in… early season hackers (of vex games) ? :stuck_out_tongue:

#6

Amazing robots as always

#7

Hello,
I couldn’t exactly tell but does 8059z have any mechanism that pushes the mobile goal into the zones. Or do you just raise it above the standoffs and then stop really fast and have it slide off?
If it does just slide off how reliable has that been?

#8

If you look at the video closely when 8059z is scoring into the 20-point zone, you will see that the back wheels are resting on the starting bar, most of the time the mobile goal will just slide down. But the chain bar mechanism is always ready to go behind the cones and give the mobile goal and stack a push if need be.

It has been very reliable.

#9

Wow, really nice bots as usual from the Singapore teams. About 8059z’s bot: why did you decide to gear 1:7 for the reverse double four bar? Seems a bit slow to me. Also, do you think the drive would work as well on four speed motors or is six needed to move with mobile goals quickly without stalling?

#10

@meng thanks for the reply. Love the idea!

#11

To add on to what @meng has said, for scoring mobile goals into the 10 point zone, the mobile goal does not slide off the intake. The robot crosses the bar before putting the stack down securely, avoiding the possibility of cones that can fall off.

There are a few reasons for this decision. Firstly, the lift is fairly tall and heavy. Considering the short span of time to build the robot, 1:7 was the safest option that ensures a reliable, considerably strong lift. Secondly, a well- assisted 1:7 lift is not that slow. It should be noted that the robot is actually quite tough to drive (extremely difficult for a single driver, unless there is significant automation of the movement of the chain bar and the scoring movement in general). Often, the “limiting factor” of the speed of the robot was actually the chain bar.

Again, 6 motors is probably the most well-balanced drive for this robot. With a rear wheel drive, and immense pressure acting on the front wheels (because of the mobile goal’s location at the front), it might be difficult to cross the 1 inch pipe satisfactorily if 4 motors were used.
The use of 6 motors also opens possibilities for defense and will certainly give one an edge in terms of moving around to collect mobile goals.

#12

Wow. I love 8059Z’s speedy way of righting fallen cones and 8059J’s wall and the strategy you use. Great stuff :slight_smile:

#13

@robobro

Just to add on… firstly, like what I have always been saying - singvex robots are always far from optimised. There simply isn’t enough time for us to try out different gear ratio.
Most probably 1:5 will work, but we also realised that like what my students mentioned, the limiting factor or bottleneck is actually the speed of the chain bar. And at the moment, the lifting speed is fast enough for the chain bar.

Secondly, something that a lot of people always forgot - more torque generally means higher acceleration. And for a short distance, there isn’t too much of a difference between higher starting speed + lower acceleration and lower starting speed + higher acceleration.
Think the former might still be a small fraction faster, but don’t think it will be significant.

And I will always err on the side of having more torque (for short distance).

#14

I wasn’t wondering if you could shed some light onto how 8059A did during the competition, being that they only deliver mobile goals with stacks. I love the idea of being a specialized robot that moves stacks, and it reminds me of the 2015 frc robot from teams rush 27. You guys are going to be a force to be reckoned with if you get pair with a good stacked

#15

Hi,
8059A was actually planning to be second picked by the first seed, but during the selection process inadvertently fell into the 8th seed’s position. with 8059J and 8076B in its alliance, it lost in the quarter finals.
But it would be quite right to say that 8059A would complement a good stacker well: Its 4 bar design means that it can move stacks already built by its alliance into the zones very easily, allowing the alliance to focus purely on stacking cones rather than scoring the stacked mobile goals. 8059A would also be able to significantly disrupt an opponent.

#16

Again… to add on to @8059_Blank … as of any specialised robots, 8059a is dependent on the type of alliances they were matched with.
As Long as their alliance was a decent stacker, they will stand a good chance of winning.
They did pretty ok in the qualifying rounds, 6-3-0.

And as what my students said - they will be a good 2nd pick.

#17

Do you think that 8059A is going to redesign for a different strategy, stick with your current configuration or improve upon the strategy

#18

Oh… definitely it will be a totally new robot.
In fact, the story behind 8059a is that - it started off with the team coming together for a Ri1D… but they ran out of time. And ended up with them putting aside the dr4b and did this specialised robot instead.

So… yes… the base was actually meant for something a lot more sinister :stuck_out_tongue:

#19

Can’t wait to see what that sinister robot will become

#20

for the 8059z chainbar, I saw that you didn’t use high strength sprockets. Is it because u guys didn’t have enough room, or was it just so because it wasn’t necessary?