A. Minimum Maneuver Time

In the MTTP for industrial robotics, minimum maneuver time [22,23] has been considered to improve the work efficiency of robots, which is also a factor for space robotics. Another key factor is to reduce the accident risk in outer space. In some cases, an urgent task should be performed in ISS, while the functional completeness of ISS should be guaranteed in advance. Component maintenance, assembly, and refueling of ISS should be finished in the shortest time, contributing to the functional completeness of ISS before performing the urgent task. Thus, urgent tasks are performed in time and the accident risk is reduced. One of the developed objectives is that the space robot is required to execute a series of tasks such as refueling with minimum maneuver time. Therefore, the end effector is required to visit a set of predefined waypoints with minimum time, which is expressed as:

$$\min F\_1 := \sum\_{j=1}^{N-1} T\_j \tag{6}$$

In Equation (6), *N* denotes the number of waypoints and *Tj* denotes the time period during which the end effector moves along the *j*th subpath, i.e., from the *j*th waypoint to the (*j* + 1)th waypoint. *Tj* is expressed as:

$$T\_{\dot{f}} = \max\_{\dot{i}} \left( t\_{\dot{f}f}^{\dot{i}} - t\_{\dot{j}\dot{s}}^{\dot{i}} \right) \tag{7}$$

In Equation (7), *i*(*i* = 1, ..., *n*) denotes the *i*th joint. *t i js* and *t i j f* denote the initial and the final moving time instants of the *i*th joint, respectively, corresponding with the *j*th subpath. The *n* joints move for different time periods due to unequal angular distances and unequal angular velocities. The maximum of *t i j f* − *t i js* (*i* = 1, ..., *n*) is defined as the time period employed by the space robot for the *j*th subpath.
