We report 370 measures of 170 components of binary and multiple-star systems, obtained from speckle imaging observations made with the Differential Speckle Survey Instrument (DSSI) at Lowell Observatory's Discovery Channel Telescope in 2015 through 2017. Of the systems studied, 147 are binary stars, 10 are seen as triple systems, and 1 quadruple system is measured. Seventy-six high-quality nondetections and 15 newly resolved components are presented in our observations. The uncertainty in relative astrometry appears to be similar to our previous work at Lowell, namely, linear measurement uncertainties of approximately 2mas, and the relative photometry appears to be uncertain at the 0.1-0.15mag level. Using these measures and those in the literature, we calculate six new visual orbits, including one for the Be star 66Oph and two combined spectroscopic-visual orbits. The latter two orbits, which are for HD22451 (YSC127) and HD185501 (YSC135), yield individual masses of the components at the level of 2% or better, and independent distance measures that in one case agrees with the value found in the Gaia DR2 and in the other disagrees at the 2{sigma} level. We find that HD22451 consists of an F6V+F7V pair with orbital period of 2401.1{+/-}3.2days and masses of 1.342{+/-}0.029 and 1.236{+/-}0.026M_{sun}. For HD185501, both stars are G5 dwarfs that orbit one another with a period of 433.94{+/-}0.15days, and the masses are 0.898{+/-}0.012 and 0.876{+/-}0.012M{sun}_. We discuss the details of both the new discoveries and the orbit objects.

Cone search capability for table J/AJ/159/233/table5 (Binary star speckle measures)

Cone search capability for table J/AJ/159/233/table8 (Visual orbital elements for six systems)

Cone search capability for table J/AJ/159/233/table7 (5-sigma detection limits for high quality nondetections)