The Nippon Screw Weight System (NSWS) is an on-site ground survey machine that examines the geotechnical engineering properties of soil. The NSWS was developed to encounter weather abnormalities and natural hazards, saving human lives.
Introduced in 2012 by the National Agriculture and Food Research Organization (NARO), the NSWS was designed to overcome problems with the standard penetration test (SPT).
NSWS was created by Kozo Okita, was the member of 311 earthquake disaster committee  of the Japanese Geotechnical Society. The society released a report in June, 2012 proposing to the Japanese government a use of NSWS to investigate the aftermath of the 2011 Tōhoku earthquake and tsunami.
The NSWS is compact, weighs 120kg, and has wheels, making it suitable for ground measurement in crowded residential areas. It costs much less than the conventional SPT test and triaxial compression test. 
NSWS can measure very soft zones, converted N-value of zero in the ground that had been considered difficult. It has 1.08cm interval.SPT conducts the test every 50cm, and 30cm interval out of 50cm is tested so the rest, 20cm, is not measured; that means 40% of an entire hole is unknown. NSWS does not suffer from such a limitation.
NSWS can prepare converted N-value, density, in-situ shear data for Stability Analysis. NSWS enables multi-point surveying due to its diagonal penetration capability and high-mobility. The multiple spots on the weak layers can be analyzed.