A device and a process for the continuous application of a refractory slurry to a surface incorporate a batch reactor (10) for the controlled mixing of the slurry, a product vessel (60) in communication with the batch reactor (10) to contain the mixed slurry, and a variable-rate spraying applicator or nozzle in communication with the product vessel and with an air supply. A controller (100) controls input to, output from, and the operation of, the batch mixer (10), and monitors batch production. The controller (100) monitors the amount of slurry contained in the product vessel (60). If the level of slurry in the product hopper is such that the product hopper cannot accommodate an additional batch of slurry, the controller interrupts batch production and resumes production when the product hopper can accept the contents of the batch reactor (10).

A vehicle includes a chassis, a drum, a load detection system, and a control system. The drum is coupled to the chassis and is configured to mix drum contents received therein. The load detection system is coupled to the chassis and includes a load sensor. The load sensor is positioned proximate to one of a forward end of the drum and a rear end of the drum. The load sensor is configured to determine a portion of a force applied by the drum to the chassis. The control system is communicably coupled to the load detection system and is configured to determine a longitudinal position of a concrete buildup in the drum based on the portion. The control system is also configured to generate at least one of a notification indicating the longitudinal position or a control signal based on the longitudinal position.

A method for determining cleanliness of a drum of a fresh concrete mixer truck. The method generally has: rotating the drum about the rotation axis with a constant torque; using a rotational speed sensor, measuring a plurality of speed values corresponding to speeds at which the drum rotates at different moments in time during said rotating; and using a controller, receiving the plurality of speed values; accessing calibration data having different reference speed values-related data associated to corresponding reference degrees of cleanliness of the drum; comparing at least some of the speed values to the calibration data; and determining a degree of cleanliness of the drum based on said comparison.

Sounds are generated by an aerial vehicle during operation. For example, the motors and propellers of an aerial vehicle generate sounds during operation. Disclosed are systems, methods, and apparatus for actively adjusting the shape of a propeller blade of an aerial vehicle during operation of the aerial vehicle. For example, the propeller blade may have one or more joints that adjust to alter the shape of the propeller blade. The altered shape of the propeller blade causes the propeller to generate different frequencies of sound as it rotates. By altering multiple propeller blades of the aerial vehicle, the different sounds generated by the different propeller blades may effectively cancel or reduce the total sound generated by the aerial vehicle, and/or alter the total frequency generated.

A concrete mixer system includes a control system configured to provide a first input to a drum drive system to rotate a drum of a concrete mixer at a target speed while the drum is empty and clean, acquire operating data regarding an operating characteristic of the drum drive system to determine a baseline operating characteristic of the drum drive system in response to the first input, provide a second input to the drum drive system to rotate the drum at the target speed following one or more uses of the concrete mixer and while the drum is empty, acquire the operating data to determine a current operating characteristic of the drum drive system in response to the second input, and provide a buildup notification indicating that there is a buildup of drum contents within the drum in response to a difference between the baseline operating characteristic and the current operating characteristic exceeding a threshold differential.

An inference system for monitoring a cementitious mixture for three-dimensional printing is provided. The inference system includes an ambient condition sensor, a temperature sensor, a moisture sensor and an image capturing device. The inference system also includes a controller coupled to the ambient condition sensor, the temperature sensor, the moisture sensor, and the image capturing device. The controller receives sensed ambient conditions, a temperature signal, and a moisture content signal. The controller receives an image feed of a portion of a cementitious mixture. The controller also receives signals indicative of a motor speed and a motor torque associated with a mixing container. The controller builds a model and determines a material suitability of the cementitious mixture using the model based on the received ambient conditions, the temperature signal, the moisture content signal, the image feed, the motor speed, and the motor torque and determines one or more corrective actions.

Described are a method and system for minimizing errors in the manufacture or management of aggregate-containing construction materials such as concrete. Aggregates used for making concrete are stored or weighed in dry bulk bin type hoppers, and conveyed from these hoppers into mixer drums which batching or mix the concrete. The hoppers or conveyor belts may contain sensor probes for measuring moisture levels in the aggregate. These sensor probes require calibration from time to time, but time and expense are required for proper calibration, leading to habitually erroneous moisture level data used in the industry on a daily basis. The present inventors believe that the smallest inaccuracies in aggregate moisture level readings can have profound effects on the properties of the resultant concrete product. To confront this long suffered problem, the present inventors surprisingly discovered that the inaccuracy of these aggregate moisture sensors, as used for evaluating the aggregate as a dry bulk material, can be detected and even addressed through the use of slump monitoring systems to evaluate the concrete slurry mix prepared from the aggregates.

Method and system to measure and monitor the grey water content in a rotating concrete mixer drum mixer truck using a sensor attached to the interior of the concrete mixer drum. By measuring the grey water content before a batching process takes place, the batched water (and cement content and admixture type and content) can be modified in order to maintain expected performance of the batched load in terms of both strength and rheology, or more simply, some or all of the grey water can be discharged from the concrete mixer drum before batching.

There are described methods and systems for handling fresh concrete inside a drum. In an aspect, a method of determining calibration data for use in determining workability of fresh concrete inside a rotating drum based on hydraulic pressure is described. This method has receiving a probe pressure value indicative of pressure exerted on a rheological probe mounted inside the drum and immerged in the fresh concrete; determining a workability value indicative of workability of the fresh concrete based on the probe pressure value and on calibration data for the rheological probe; receiving a hydraulic pressure value indicative of pressure of a hydraulic fluid used for rotating the drum; and determining hydraulic calibration data by associating the hydraulic pressure value and the workability value to one another.

The present invention provides a method and system for detecting hardened concrete buildup in a mixer drum which is substantially devoid of plastic concrete. An exemplary method involves monitoring the hydraulic pressure required to rotate the drum through at least two successive rotations at constant speed, using a hydraulic pressure sensor on hydraulic charge side, discharge side, or preferably both sides of the hydraulic motor which turns the mixer drum; and detecting when the pressure/time data curve indicates eccentric behavior of the mixer drum, whereby an alarm or other indication is provided to confirm that the hardened concrete buildup in the truck is not acceptable. The buildup detection method and system of the present invention does not require the use of an automated slump monitoring system, but can be implemented in combination with such systems with favorable results and advantages.