This question hopes to make a space tug crew's life tolerable.

A supply pipeline links two civilizations. Due to the long travel time between the ends, cargo is "thrown" at the other side in unmanned and unpowered cargo barges, save for minor attitude, yaw and pitch thrusters. Tugs push a barge up to 0.1c and release it, then reverse to catch an inbound barge coming at them at 0.1c. Barges are timed like this to prevent a tug going out or coming back with no payload.

(Space tug)

The human crew is going to be subjected to an environment for a long time, and will be doing this repeatedly. My goal is to:

• Minimize the duration of each operation

• Minimize exposure to either low or high g-force acceleration.

Below is the velocity curve for one operation: $$\text{Accelerate outbound payload:} f(a) = t_0 \rightarrow t_1 \\ \text{Release and reverse direction: } f(b) = t_1 \rightarrow t_2 \\\text{Catch and decelerate incoming payload: }f(c) = t_2 \rightarrow t_f$$

(Velocity curves are not drawn to scale and are not required to be linear)

I need to make the sum of these acceleration curves $f(a)+f(b)+f(c)$ as short as possible, while preventing unreasonable forces on the crew. So the acceleration constraints are:

• Acceleration through $f(a), f(c)$ can be no more than 1.2g

• Acceleration through $f(b)$ should remain at 1.2g for most of the time, with no more than 1-hour bursts at 2g (possibly at night time when everyone is lying down, with forced oxygen masks)

What is the shortest duration for this trip $t_0 \rightarrow t_f$, and could a physically fit crew do this job twice per year?

I am also curious what time dilation differences this crew would experience each flight

posted over 4 years ago

Vogon Poet‭

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