SDS 4MKi L1 vs L2

Hi

We used the SDS 4MKi L1 NS we had a great season. I was just wondering if the teams using the L2 was able to use all the extra speed .

Thank you in advance

Yes, last year we had neos and a ~100 pound bot and had no issues accelerating. We are running L2.5 with Krakens this year and a 100 pound bot and have no issues.

My team has been using L2 on a 124.5 lb robot with krakens and has had no issues with acceleration.

I think L1 is just not really needed for recent games as generally you don’t push against robots on swerve you try and use mobility to dance around them. On an open field L2 is fine for a max weight robot to the best of my knowledge. Being faster and accelerating faster is just more beneficial from what I’ve seen.

1 Like

The added torque of L1 can really separate a defensive swerve bot, it’s a lot slower but when a L3 robot for example is pinned it can cause major issues.

This year team 67 was pinned during a match and they attempted to swerve away with their L3 swerve and tripped a breaker due to the amount of current being used in fighting a L1 bot. Additionally L1 robots sitting in front of the enemy speaker tend to receive penalty points due to offence initiating contact in attempting to shoot (this doesn’t work really for adjustable shooter bots).

We swapped from L1 to L3+ this season (16T conversion kit) and would highly recommend swapping to L3. The difference between L1 and L2 may be noticeable, but for about $40 an upgrade, I’d suggest going straight to L3. We found the 16T conversion kit to be worth the cost and effort as well because we can simply drive faster than most other robots. Acceleration has not been a problem but he robot is noticeably less responsive to stick movement - it takes some driver adjustment.

3 Likes

I mean waiting for a pin count vs being overall slower and having a higher chance to not even get caught in the pin is better. For defense this year I didn’t really see pins as the scary part of defense compared to a wider, faster robot that just gets in the way and matches L2 bots or overpowers L3 bots.

Truthfully, I would put the discussion as L2 vs L3 gearing. Even with a 135lb robot after battery and bumpers at L3 gear ratio with Kraken drive motors and a coefficient of friction of 1.4, the robot is still seeing wheel slip. The calculated slip is at 73A per motor(for the first 0.2ish seconds). With an L2 gearing, you have a similar amount of slip time, but the motor current is down to 66A. Higher wheel coefficient of friction will decrease slip, but increase current to the motor. So balancing the grippiness of the wheel with how much current the motors are allowed to take is the balancing game teams need to play, such that the main breakers are not being tripped.

I’m of the opinion that wheel friction and current limiting in code is going to be the biggest difference you have in how well you can play defense, since a team with slippery wheels is going to get pushed around by a team with grippier wheels, since all the robots have enough power at the wheels to cause wheel slip when pushing another robot at this point with brushless motors.

2 Likes

One of our students said that they saw a chart that listed recommended weights for L1 to L4 gearing, but no-one can find it on-line anywhere. Does anyone know where this list is if it exists?

Thx.

Yes, L2 is absolutely worth it. L1 is often traction limited which means that you can’t make use of all of the extra torque it provides because the wheels would slip, meaning that potential motor power is just being wasted. The full speed of L2 is very usable even in acceleration-heavy games such as 2022