Looking for Striker Stats for the ATV

[AnotherDilbert]

Coming late to this party, but has anyone else noticed that the whole concept of a TRANSMISSION in Striker and Book8: Robots and MegaTraveller is a lot of wasted effort to add less than 1% to the cost or weight of the final vehicle? It requires lots of special calculations that get dropped when you round off the final values for 3 decimal place use in a game. I have started just ignoring it.

Sure it's only a few percent, for a wheeled vehicle at higher TL, but so are a lot of other components...

For this Striker wheeled TL7 truck its about 2% of volume and mass and 3% of the cost.


At for tracked vehicles and especially lower TLs it's a lot more. For a vaguely similar tracked TL5 vehicle it's about 10% of volume/mass and 20% of the cost:



As it is just a straight fraction of engine power, a single multiplication, I don't see much added complication. Determining engine power with the correct scale factor is more complicated...

 

[AnotherDilbert]

LBB8 is a bit worse:

LBB8, p26:
Wheels
_ Suspension: Wheels require at least 15% of chassis volume.
_ Transmission: One unit of transmission is required for each kilowatt of power plant output. The total transmission volume must fit within the chassis volume.
_ For example, a robot has a 300 liter chassis and a power plant output of 90 kw. The wheel suspension takes a minimum of 45 liters, which weighs 45 kg and costs Cr540. The 90 units of wheel transmission take 27 liters, use 27 kw, weigh 45 kg, and cost Cr1350.

Seems like 15% of volume for the suspension and another ~10% for the transmission. Hardly insignificant?

 

[atpollard]

LBB8 is a bit worse:

Seems like 15% of volume for the suspension and another ~10% for the transmission. Hardly insignificant?

CT Errata (DonM):
Page 26, Wheels, Suspension (correction): Wheels require at least 1.5% of chassis volume.
Page 26, Tracks, Suspension (correction): Tracks require at least 2.0% of chassis volume.

However, I freely admit that I have no idea what this Errata means:
Page 27, Locomotion: Transmissions (Legs, Tracks, Wheels) (omission): Note the power requirements: each leg, 40kW; track, 30kW, wheels, 20kW. Each unit is per kW of power plant output.

[It appears to state that for each 1 kW of PP, my wheels need 20 kW of PP ... high on the list of things that make you go "SAY WHAT???" I think it meant to be the other way around ... 20 kW of power to the WHEELS for each MW of power plant output = 0.02 kW of power to the WHEELS for each kW of power plant output. However, who knows for sure what was intended.]

 

[AnotherDilbert]

CT Errata (DonM):
Page 26, Wheels, Suspension (correction): Wheels require at least 1.5% of chassis volume.
Page 26, Tracks, Suspension (correction): Tracks require at least 2.0% of chassis volume.

Yes, "at least", but you might want to use more to reduce ground pressure, in order to improve terrain capability, see Striker.
Note that suspension volume does not affect transmission volume.

However, I freely admit that I have no idea what this Errata means:
Page 27, Locomotion: Transmissions (Legs, Tracks, Wheels) (omission): Note the power requirements: each leg, 40kW; track, 30kW, wheels, 20kW. Each unit is per kW of power plant output.

[It appears to state that for each 1 kW of PP, my wheels need 20 kW of PP ... high on the list of things that make you go "SAY WHAT???" I think it meant to be the other way around ... 20 kW of power to the WHEELS for each MW of power plant output = 0.02 kW of power to the WHEELS for each kW of power plant output. However, who knows for sure what was intended.]

Recheck the version of the errata. I get:

Consolidated CT Errata 1.2 (03/31/15), p21:
_ Page 27, Locomotion: Transmissions (Legs, Tracks, Wheels) (omission): Note the power requirements: each leg, 0.4kW; track, 0.3kW, wheels, 0.2kW. Each unit is per 100kg of robot mass.

Instead of per kW of power plant output, it's now per 100 kg of mass.


So, for a two-legged robot with a chassis volume of 50 l and an estimated mass of 100 kg we get:
Suspension: Two legs à 5% is 10% of volume, so 5 l (external), 5 kg.
Transmission: At 100 kg, one unit of transmission is required (regardless of the number of legs?), using 2×0.4 kW = 0.8 kW, 0.5 l, and 1 kg.
Power: For a 30 h duty cycle, it would require 0.8 kW × 30 h = 24 kWh = 24 l, 24 kg battery at TL-12.

So, just for locomotion we would use 5 kg (suspension) + 1 kg (transmission) + 24 kg (power) = 30 kg for a 100 kg robot.
Note that the transmission gives the power requirement for the locomotion, so is necessary to calculate.


The change to units of transmission based on mass is more "realistic", but more complicated as we basically calculate in volume, but with a feedback loop in mass. For every change in mass, the power plant needs to be recalculated...

 

[atpollard]

Recheck the version of the errata. I get:

I definitely need a copy of the newer errata.

 

[AnotherDilbert]

I definitely need a copy of the newer errata.

Why is the errata not publicly available? Is there some copyright issue?

I.e. can I share it here in the file library?

 

[atpollard]

Why is the errata not publicly available? Is there some copyright issue?

I.e. can I share it here in the file library?

No, it is available here. [It is even in the COTI Library]. I just had an old (2013) copy from my old CD.