IA:
some suggection for this subject , you need 6 - 8 pcs of loadcell with a very good platform design to suffer the vibration and make a very fast sample rate ,base on your information and in motion scale your system is only 3 digit 20.0, +/-0.5 error free it should not be very hard to do , only the most importen thing is make sure that your platform ( the motion axle) have a very good balance adjustment in each corner --- at least 3 section)
have fun