PlanetVac uses pressurized gas to push regolith into a sample container (effectively acting like a planetary vacuum cleaner). Because of the low pressures on Mars, the Moon, and asteroids, the technique is extremely efficient because the efficiency is related to the ratio of the pressure of the gas you are using to the ambient pressure. Landers typically have high pressure Helium already on board, used to pressurize the fuel tanks, which could be used as the gas.
A report on the project was given at a conference this week: PlanetVac at the IEEE Aerospace Conference – The Planetary Society
PlanetVac system on Mars soil simulant
Honeybee Robotics’ PlanetVac system, sponsored by The Planetary Society,
after successful testing in vacuum chamber, sits on Mars soil simulant that it
successfully sampled. Credit: Honeybee Robotics
This video shows prototype tests in a vacuum chamber:
And here is a video from a 2012 visit to the Honeybee Robotics factory: