A Badge for Every Robot

Medium — logic-grid deduction puzzle

Four volunteers each looked after a robot with its own task and picture badge at the arena's demonstration tables.

At the humanoid robot games, the arena had a corner where visitors could meet the robots up close. Four volunteers looked after one robot each. Linyu and Wenbo were engineers who built robots for a living. Zihan and Xiaotong were dancers who had come along to help for the day. The four tables stood in one row, with the first by the entrance and the fourth at the far end. Each volunteer had a different table, and each robot showed off a different task and wore a different picture badge. The badges were there for the visitors, who found a moon or a fish far easier to remember than a model number.

Clues

1. The robot with the fish badge stood further down the row than the robot with the moon badge.
2. The sorting robot, the second table and the fish badge all belonged to three different volunteers.
3. Neither Zihan nor Xiaotong looked after the boxing robot.
4. Only one of these was true: the carrying robot stood at the third table; Xiaotong looked after the carrying robot; Linyu worked at the third table.
5. The robot that showed off sorting wore the peach badge.
6. Of the robots wearing the peach and fish badges, one stood at the third table and the other was looked after by Linyu.
7. One of Wenbo and Xiaotong worked at the third table, and the other worked at the fourth table.

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