Ping and oblique angles

I'm sure this is not a new issue. My robot uses a ping to look for obstacles and then when found, it stops sweeps 180 degrees (10 segments) looking for a clear path. I am having a problem with surfaces at oblique angles to the ping in that it can't correctly determine the distance. I am pretty sure that I would have s the same issue with the Sony IR sensor, but not sure. Has anyone run into a solution for this problem? The sensor works perfectly in every other way.

Charlie

Not sure what I could have done to avoid that but just trying to come up with something here: will putting a vertical scan motor help?

will putting a vertical scan motor help

I'm afraid I don't understand. What do you mean by vertical scan motor? I am open to any suggestion.

Just my thought: Scan horizontally and find an obstacle, then scan vertically to see if the obstacle is changing slightly (can't pass) or rapidly disappears (ramp). You need a motor to scan up and down.

Not real sure how that would help. If the problem is that the ping is bouncing off in another direction like light in a mirror, then it seems that it would do that even if I scanned up and down. I will have to think about that some more.

Thank you for your suggestion, none the less. Anything that causes to me to think from another angle is a good suggestion.