Input device and game system including the input device

A music game system comprising:

• an input device provided with at least one operation portion for imitating a stringed instrument, the input device being located within an operational space and including a body portion, a neck portion extending from the body portion, a head portion provided to a leading end of the neck portion;
• and an acceleration device that can detect acceleration of the input device;
• and
• a display device that outputs and displays a game screen;
• an audio output device that outputs and plays back game sounds;
• a music composition data storage device that stores music composition data for playing back music;
• a music playback device that plays back the music from the audio output device based on the music composition data;
• a sequence data storage device that stores sequence data describing operation moments of the operation portion during the game;
• and
• an operation guiding device that (i) instructs operation of the input device to a player by determining a plurality of operation moments of the input device included in a predetermined time period from a current time toward a future time in a piece of music being played in a game, (ii) displays an operation instruction sign corresponding to each of the plurality of determined operation moments and an operation reference sign corresponding to the current time arranged in a layout along a time axis on a game screen, and (iii) produces a relative displacement between the operation reference sign and each operation instruction sign according to progress of time in the piece of music so that a location of each operation instruction sign coincides with a location of the operation reference sign at the moment along the time axis that the respective operation moment of the input device is expected;
• wherein the operation guiding device includes a motion guiding device that (i) instructs the player to perform a predetermined motion of the input device by displaying a motion instruction sign corresponding to a moment at which the player should carry out the predetermined motion of the input device, displayed in the layout along the time axis on the game screen, and (iii) produces a relative displacement between the motion instruction sign and the operation reference sign according to the progress of time in the piece of music so that a location of the motion instruction sign coincides with a location of the operation reference sign at the moment along the time axis that the predetermined motion is expected, wherein the predetermined motion defines a motion of the input device detected by the acceleration device between two positions located within the operational space.