Patent ID: 8118473

Claim:
A system for calculating and reporting slump, comprising: a delivery vehicle having a mixing drum and hydraulic drive for rotating the mixing drum; a fluid supply and a flow valve coupling said fluid supply to the mixing drum; a rotational sensor mounted to the mixing drum and configured to sense drum activity in the form of a rotational speed of movement of the mixing drum; a hydraulic sensor coupled to the hydraulic drive and configured to sense drum activity in the form of a hydraulic pressure required to turn the mixing drum; and a programmable processor coupled to the flow valve, rotational sensor and hydraulic sensor, and a program memory storing a program that causes the processor to compute a slump measure for a mixture within the mixing drum using information from the sensors, wherein the rotational speed of movement of and hydraulic pressure applied to the mixing drum over a period of time are used in determining when mixing is complete and in calculating the slump of the material within the mixing drum, wherein the processor determines whether to discharge fluid into the mixing drum based upon the slump of the material.