摘要 |
<p>A head mountable apparatus 20 such as a HUD has a frame supporting electrical and/or optical devices (150,160 fig 2), a cable 82,84 connecting the electrical and/or optical devices (150,160, fig 2)to an external separate device 300. A detector for sensing head movements of a user 10 used to determine if the cable 82,84 may become wrapped around the user's 10 body or become tangled. The detector may be an accelerometer or gyroscope (400, fig 7) or a camera (222, fig 8), or may be performed by sensors (470, fig 9) in the cable 82, 84. A warning may be provided to the user either visually or audibly and may indicate which way the user should move to prevent the cable winding or wrapping or becoming tangled.</p> |