Concrete placement vehicle control system

Description of equivalent WO 2005011943 A2

CONCRETE PLACEMENT VEHICLE CONTROL SYSTEM AND METHOD

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

[0001 ] This application is a continuation-in-part of U .S. Ser. No. 09/927,946, filed August 1 0, 2001 , pending, which is a continuation-in-part of U.S. Ser. No. 09/384,393, filed August 27, 1 999, now U.S. Pat. No. 6,421 ,593, which is a continuation-in-part of U.S. Ser. No. 09/364,690, filed July 30, 1 999, abandoned, each of which is hereby expressly incorporated by reference. This application also claims priority to U.S. Patent Application. No. 1 0/326,862, filed December 1 9, 2002, which claims priority to U.S. Prov. No. 60/342,292, filed December 21 , 2001 , each of which is also hereby expressly incorporated by reference. This application further claims priority to U.S. Prov. No. 60/491 ,41 1 , filed July 31 , 2003, which is hereby expressly incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] The present invention relates generally to the field of concrete placement vehicles. More specifically, the present invention relates to concrete placement vehicle control systems for concrete placement vehicles. [0003] Various vehicles, vehicle types and configurations of vehicles are known for use in placement of concrete. Concrete placement vehicles often include a mixing drum rotatably mounted to a flatbed of an industrial vehicle. The mixing drum includes mixing blades affixed to the interior of the drum in a spiral pattern to either charge (mix) or discharge concrete. A delivery system usually includes a chute or pumping hose placed at an opening in the mixing drum. Rotation of the drum for both mixing and discharging operations is controlled by a mixing drum motor mounted to the flatbed of the vehicle and connected to the mixing drum. [0004] In operation, concrete materials are added to the mixing drum to initiate a concrete mixing process. Concrete materials can include at least cement, sand, aggregate, and water. Following addition of materials, the mixing drum is rotated in a first direction by the mixing drum motor to mix the materials and produce concrete. The rotation of the mixing drum in a direction to mix the materials therein is referred to as a charging rotation. [0005] During delivery, concrete is removed from the drum through a mechanical or forced pressure system for delivery. Using a mechanical system, the mixing drum is rotated in a second direction, referred to as a discharging rotation. The concrete can be delivered from the mixing drum to a concrete delivery chute extending outward from an opening in the drum to the point where the concrete is to be placed. Alternatively, the opening in the mixing drum can be connected to a hose, the outlet of which is placed at the point where concrete is to be delivered. [0006] All aspects of the above-described operations related to a concrete mixing and delivery system may be controlled by a human operator. The human operator places the concrete materials in the mixing drum, controls the mixing drum motor to rotate the mixing drum to mix the concrete mixing materials, and controls the concrete delivery system to deliver the concrete. [0007] In some instances, the human operator is not able to continuously and effectively control and monitor the concrete mixing and delivery system while performing operations associated with the mixing and delivery process. For example, during concrete discharging, the operator may control the chute or hose outlet from a control panel locate on the vehicle to ensure the proper placement of the concrete load. The operator must also control the rotation speed of the mixing drum to control the flow of the concrete. However, the drum rotation controls and the delivery system controls may be in separate locations making it difficult for the operator to easily control both systems. [0008] Further, the operation of the mixing drum motor can be dependent, at least in part, on the engine speed of a concrete placement vehicle. For example, at high mixing drum rotation speeds, the RPM of the engine for the concrete placement vehicle must be sufficiently high to power the mixing drum motor. Accordingly, in order to increase the mixing drum rotation speed, an operator is required to first increase the engine RPM of the concrete placement vehicle and then increase the rotation speed of the concrete mixing drum. Such an operation causes a loss in efficiency. [0009] Yet further, while driving concrete from an origin point to a delivery site, the operator is generally not able to monitor and control the state of the concrete in the mixing drum. The concrete may become too dry or separate during the time the operator is driving to the delivery site. Accordingly, the operator is forced to take remedial action upon arriving at the delivery site to correct any problems that may have occurred during the drive from the origin site to the delivery point causing a loss in efficiency. [0010] Accordingly, it is desirable to provide a control system for a concrete placement vehicle which overcomes one or more of the above- mentioned problems. Advantageously, such a control system would enhance many aspects of concrete placement. The techniques below extend to those embodiments which fall within the scope of the appended claims, regardless of whether they provide any of the above-mentioned advantageous features.

SUMMARY OF THE INVENTION

[001 1 ] One embodiment of the invention relates to a concrete placement vehicle. The concrete placement vehicle includes a concrete mixing and placement system, at least one vehicle sensor configured to monitor a characteristic of the concrete placement vehicle and at least one concrete system sensor configured to monitor a characteristic of the system for mixing and placing concrete. The vehicle further includes a control system configured to control the operation of the concrete placement vehicle and the concrete mixing and placement system based on inputs received from the at least one vehicle sensor and the at least one concrete system sensor. [001 2] Another embodiment of the invention relates to a concrete placement system. The concrete placement system comprises a plurality of components for mixing and placing concrete including at least a first component and a second component, each component including an operational state. The system further includes a control system configured to determine the operational state of a first component and to control the first component based on an operational state of the second component. [0013] Another embodiment of the invention relates to a concrete placement vehicle. The concrete placement vehicle comprises a concrete mixing and placement system comprises a mixing motor mounted to the concrete placement vehicle and configured to rotate a concrete mixing drum, a concrete delivery chute configured to be controlled by at least one actuator, and a power distribution and control system. The power distribution and control system further includes a power source, a power transmission link, a plurality of output devices and a plurality of input devices. The plurality of output devices includes a plurality of actuators capable of adjusting the position of the concrete delivery chute. The plurality of input devices includes a plurality of position indicators capable of providing position information pertaining to the position of the concrete delivery chute. The system further includes a communication network, and a plurality of microprocessor-based interface modules. The plurality of interface modules may be coupled to the power source by way of the power transmission link and interconnected to each other by way of the communication network. The plurality of interface modules may also be coupled to the plurality of input devices and to the plurality of output devices by way of respective dedicated communications links. The plurality of interface modules include an interface module that is coupled to at least some of the plurality of position sensors and at least some of the plurality of actuators, wherein the plurality of interface modules, the plurality of input devices, and the plurality of output devices are distributed throughout the concrete placement vehicle. Further, each respective interface module is locally disposed with respect to the respective input and output devices to which the respective interface module is coupled so as to permit distributed data collection from the plurality of input devices and distributed power distribution to the plurality of output devices. [0014] Another embodiment of the invention relates to a method of controlling a concrete placement vehicle. The method comprises receiving a control signal for a first component of a system for mixing and placing concrete, determining an operational state of at least one additional component of the system for mixing and placing concrete, and controlling the first component of the system for mixing and placing concrete based on the control signal and the operational state of at least one additional component.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Fig. 1 is a perspective view of a concrete placement vehicle having a control system according to one embodiment of the present invention; [0016] Fig. 2 is a block diagram of a concrete placement vehicle control system according to an exemplary embodiment; [0017] Fig. 3 is a block diagram of a concrete placement vehicle control system capable of controlling the identified components of a concrete placement vehicle according to an exemplary embodiment; [0018] Fig. 4 is a block diagram showing selected aspects of the control system of Fig. 3 in greater detail according to an exemplary embodiment; and [0019] Fig. 5 is a flowchart showing a method for automatically mixing concrete according to an exemplary embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Referring to Fig. 1 , an exemplary embodiment of a concrete placement vehicle 1 0 is illustrated. By way of overview, the concrete placement vehicle 1 0 generally includes a chassis, an engine, and a vehicle body mounted on the chassis, with the chassis and the vehicle body in combination including an operator compartment 1 6 capable of receiving a human operator. The operator compartment 1 6 further includes steering and throttle controls for receiving operator inputs to control the movement of the concrete placement vehicle 1 0 along a road. A concrete placement system 1 1 0 may be mounted to the concrete placement vehicle 1 0, and can be configured to transport and deliver a load of concrete. Delivery of a concrete load includes discharging the concrete load from the concrete placement system 1 1 0. [0021 ] It should be understood that Fig. 1 merely illustrates one embodiment, and that the concrete placement vehicle 1 0 may have a variety of configurations. For example, in Fig. 1 , the concrete placement vehicle 1 0 includes a rear discharging concrete placement system; however, it should be understood that the applicability of the present disclosure is not limited to rear discharging concrete placement systems. Rather, other types of concrete placement systems may be used such as front discharging systems, concrete pumping delivery systems, etc. The teachings herein do not depend on the configuration, construction, size, or assembly of the concrete placement vehicle 10. [0022] The concrete placement system 1 1 0 may include a concrete mixing system 1 1 1 and a concrete delivery system 1 20. Concrete mixing system 1 1 1 can include a concrete mixing drum 1 1 2, a mixing motor 1 1 4, a water storage system 1 1 6, and a cooling system 1 1 8. Concrete delivery system 1 20 can include a concrete delivery chute 1 22, a delivery chute rotation motor 1 24 and a delivery chute elevation motor 1 26. [0023] Concrete mixing drum 1 1 2 can be configured according to a variety of sizes and shapes. The concrete mixing drum 1 1 2 can be sized and shaped based on a variety of factors such as the strength of the chassis of concrete placement vehicle 1 0, local regulations and weight requirements, average concrete load size, or any other factors. Concrete mixing drum 1 1 2 typically includes a set of mixing blades placed within the interior of concrete mixing drum 1 1 2 (not shown) . The concrete mixing blades can be fixedly mounted to the interior walls of concrete mixing drum 1 1 2 and configured to optimize the agitation and mixing of concrete materials placed within concrete mixing drum 1 1 2. The concrete mixing blades are further mounted such that rotation of the mixing drum 1 1 2 in a first direction will mix the contents of the drum (hereinafter referred to as charging or mixing), while rotation of the mixing drum 1 1 2 in a second direction will cause the content of the drum to delivered from drum 1 1 2 through an opening in drum 1 1 2. According to an exemplary embodiment, mixing drum 1 1 2 is a McNeilus manufactured by McNeilus Companies, Inc. of Dodge Center, MN. Exemplary mixing drums are shown in U.S. Pat. Nos. 5,056,924, 5,378,061 and 5,427,449, all of which are assigned to the assignee of the present application and are expressly incorporated herein by reference. [0024] Mixing drum 1 1 2 further includes a drum opening configured and sized according to concrete delivery needs. For example, a larger opening may be desirable increase the speed of delivery of concrete from concrete mixing drum 1 1 2 or a smaller opening may be desirable to decrease loss of moisture content from a concrete load. Concrete mixing drum 1 1 2 is mounted to the concrete placement vehicle 1 0 and coupled to concrete mixing motor 1 1 4. [0025] Concrete mixing motor 1 1 4 may be any motor type configured to rotate concrete mixing drum 1 1 2. According to an exemplary embodiment, concrete mixing motor 1 1 4 is sized and configured based upon the configuration and size of concrete mixing drum 1 1 2. According to an exemplary embodiment, mixing motor 1 1 4 is a hydraulic motor activated by a hydraulic pump (not shown) . The hydraulic pump can be powered by the engine of concrete placement vehicle 1 0. [0026] Concrete mixing motor 1 1 4 is mounted to the chassis of concrete placement vehicle 1 0 and coupled to concrete mixing drum 1 1 2. Mixing motor 1 1 4 can be coupled to concrete mixing drum 1 1 2 through a drum transmission (not shown) . [0027] According to an exemplary embodiment, concrete mixing motor 1 1 4 can rotate concrete mixing drum 1 1 2 at a variety of speeds. The speed at which concrete mixing motor 1 1 4 rotates concrete mixing drum 1 1 2 can be selected based on a variety of criteria such as the characteristics of the concrete load contained within concrete mixing drum 1 1 2, a desired rate of delivery of the concrete load through the opening in concrete mixing drum 1 1 2, the state of the concrete contained within concrete mixing drum (e.g. an unmixed state, a mixing state, a ready state, etc.) and so on. [0028] Water storage system 1 1 6 can be any system for storing and dispensing water. According to an exemplary embodiment, water storage system 1 1 6 can be mounted to the chassis of concrete placement vehicle 1 0. Provision of a water storage system on concrete placement vehicle 1 0 allows an operator to add water to a concrete load within concrete mixing drum 1 1 2 at any time and in any location. For example, at a concrete origination site, concrete mixing drum 1 1 2 may be filled with a mixed concrete, and a water storage system may be filled with water. Concrete placement vehicle 1 0 may be driven to the concrete delivery site and the water may be mixed with the dry concrete materials at the site to optimize the characteristics of the concrete load. For example, if a concrete load within concrete mixing drum 1 1 2 has become too dry during transportation, water storage system 1 1 6 can be used to add additional moisture to the concrete load. [0029] According to yet another exemplary embodiment, concrete placement system 1 1 0 can include a cooling system 1 1 8 mounted on the chassis of concrete placement vehicle 1 0. During mixing of a concrete load, particularly a load known as a low slump load, in which the moisture content of the concrete is relatively low, components of concrete mixing system 1 1 1 and concrete placement vehicle 1 0 can generate an excessive amount of heat. A cooling system included in concrete placement system 1 1 0 can be used to reduce the amount of heat generated by system 1 1 0 and/or vehicle 1 0. Advantageously, concrete loads having low slump characteristics can be mixed and/or delivered for more extended periods without damaging concrete placement vehicle 1 0 or components of concrete placement vehicle 1 0. [0030] The components, subsystems, and operations described above with reference to concrete mixing system are described for illustrative purposes only. According to alternative embodiments, concrete mixing system 1 1 1 can include more, fewer, or different sub-systems or components than described above. Further, the sub-systems and components can perform more, fewer, or different functions than described above. [0031 ] Referring now to concrete delivery system 1 20, concrete delivery chute 1 22 includes a first end mounted proximate to the opening in concrete mixing drum 1 1 2 and a second end that is movable to position near a concrete delivery point according to an exemplary embodiment. According to an exemplary embodiment, concrete delivery chute 1 22 further includes at least one hinged portion located along the length of concrete delivery chute 1 22 such that chute 1 22 can be folded during transportation, and unfolded during concrete delivery. According to an alternative embodiment, delivery chute 1 22 can include multiple chute sections that may be assembled during concrete placement and stored during transportation. [0032] Concrete delivery chute 1 22 is mounted to concrete placement vehicle 1 0 at the first end proximate to the opening in concrete mixing drum 1 1 2. Concrete delivery chute 1 22 is rotatable on the mounting point in a semicircular arc such that the second end of the concrete delivery chute can be moved to a desired concrete delivery point. Rotation of delivery chute 1 22 through the semicircular arc can be controlled by the delivery chute rotation motor 1 24. Concrete delivery chute 1 22 is further movable to raise or lower the second end of delivery chute 1 22. Elevation of delivery chute 1 22 can be controlled by the delivery chute elevation motor 1 24. According to an alternative embodiments, the rotation and elevation control of concrete delivery chute 1 22 can be hydraulically driven or controlled through manual operator intervention. [0033] As shown in Fig. 1 , concrete delivery system 1 20 can be mounted on the rear of concrete placement vehicle 1 0 such that concrete is delivered from the rear of concrete placement vehicle 1 0. According to an alternative embodiment, the concrete delivery system 1 20 can be configured such that the concrete delivery system 1 20 is mounted to the front of concrete placement vehicle 1 0 such that concrete delivery chute 1 22 extends outward from the front of concrete placement vehicle 1 0. Advantageously, a front- mounted concrete delivery system 1 20 allows a driver to control delivery of concrete from within operator compartment 1 6. [0034] Referring to Figs. 2 and 3, a concrete placement vehicle control system 1 30 is illustrated according to an exemplary embodiment. Referring first to Fig. 2, Fig. 2 is an overview of the preferred control system 1 30 for controlling the concrete placement vehicle 1 0 and/or its various components such as concrete mixing motor 1 1 4 or concrete delivery system 1 20. The control system 1 30 includes a plurality of interface modules 1 31 a- 1 31 f (collectively, "the interface modules 1 31 "), concrete mixing and delivery I/O devices 1 40 and 1 42, and other vehicle I/O devices 1 50 and 1 52 and one or more operator interfaces 1 44a and 1 44b (collectively, "the operator interfaces 1 44") . [0035] The control system 1 30 may be implemented in a variety of ways. In a preferred embodiment, control system 1 30 controls all or a large majority of the operations and components of the concrete placement vehicle. Separate engine, transmission, brake and tire inflation control systems may be provided, however, such control systems are preferably coupled to the control system 1 30 by way of an additional communication network. The control system 1 30 may also control other equipment on the concrete placement vehicle 1 0 such as a water storage system or a cooling system. In an alternative embodiment, control system 1 30 may be implemented to control only one aspect of the concrete placement vehicle 1 0 such as the concrete delivery system 1 20. Control system 1 30 may also comprise multiple smaller control systems that are interconnected or separate. In an exemplary embodiment, control system 1 30 is an electronic control system that is microprocessor based. [0036] The operator interfaces 1 44a and 1 44b each include a display 1 46a and 1 46b respectively (collectively, "the displays 1 46") and input devices 1 48a and 1 48b (collectively, "the input devices 1 48") . Operator interfaces 1 44 may be used to receive input from an operator and provide access to functions and/or information, such as diagnostic or concrete characteristic information. The operator interfaces 144 may be located in a variety of positions around the concrete placement vehicle 1 0. For example, the operator interface 1 44a may be located in the operator compartment 1 6 of the concrete placement vehicle 1 0 and the other operator interface 1 44b may be located at another location, such as a rear or side location of the concrete placement vehicle 10. In addition, the concrete placement vehicle 1 0 may be configured with more or fewer operator interfaces 1 44. For example, the concrete placement vehicle 1 0 may be configured to include an operator interface 144 in an operator compartment 1 6 and also include an operator interface 1 44 on each side of the concrete placement vehicle 10. Distributing the operator interfaces 1 44 in various locations around the concrete placement vehicle 1 0 allows the operator or operators multiple access points to control the operation of the concrete placement vehicle 1 0 without requiring the operator to enter the operator compartment 1 6 each time. [0037] According to an alternative embodiment, an operator interface 144 may be a remote device, such as a remote control or a handheld computing device, such as a personal digital assistant (PDA). The remote device may communicate with concrete placement vehicle 10 using wired or wireless connections. An exemplary wireless connection may include a wireless link using the Bluetooth Network protocol between the handheld computing device and one of the interface modules or control system 1 30. The remote device may be configured such that the operator is provided the same functionality and information as if positioned with operator compartment 1 6 and a hardwired link is used. [0038] As discussed in greater detail in connection with Fig. 3, the concrete mixing and delivery I/O devices 1 40 and 1 42 include actuators 1 32c-1 32f (collectively, "the actuators 1 32"), sensors 1 34c-1 34f (collectively, "the sensors 1 34"), limit switches 1 36c-1 36f (collectively, "the limit switches 1 36"), and other devices used to control concrete placement vehicle 1 0 and/or its various components such as concrete mixing motor 1 1 4 or concrete delivery system 1 20. As shown in Fig. 3, the actuators 1 32, sensors 1 34, and limit switches 1 36 may be used to control the systems and components disposed on concrete placement vehicle 1 0, such as the mixing motor 1 1 4, the concrete delivery chute 1 22, the water storage system 1 1 6, and the cooling system 1 1 8. It should be understood that other aspects of the concrete placement vehicle 1 0 (e.g. vehicle lighting, etc.) may be controlled in addition to those shown in Fig. 2, for example through other vehicle I/O devices 1 50 and 1 52. [0039] With regard to the mixing motor 1 1 4, in a preferred embodiment, a rotation speed sensor 1 34c may measure the rotation speed on concrete mixing drum 1 1 2. Also, a limit switch 1 36c or sensor 1 34c may be used to ascertain whether mixing motor 1 1 4 is at or near a defined overheat point such as, for example, when concrete drum 1 1 2 is filled with a load of concrete having low-slump characteristics. In another embodiment, a sensor 1 34c may be used to determine the rotation speed of concrete mixing drum 1 1 2 through mixing motor 1 1 4 to determine whether the rotation speed is desirable based on a characteristic associated with the concrete load. For example, if the concrete load is a low-slump load, it may be desirable to maintain a fairly high drum rotation speed to prevent the concrete load from setting prematurely. [0040] With regard to the concrete delivery chute 1 22, in a preferred embodiment, a position sensor 1 34d measures rotation of concrete delivery chute 1 22 along the semicircular arc. Also, a limit switch 1 36d or position sensor 1 34d may be used to ascertain whether the concrete delivery chute 1 22 is at or near its mechanical stops such as, for example, when a hydraulic cylinder reaches its end points. [0041 ] With regard to the water storage system 1 1 6, in a preferred embodiment, a sensor 1 34e or limit switch 1 36e may be used to determine the amount of water available for delivery. Likewise, a limit switch 1 36f or sensor 1 34f may be used to ascertain the cooling status of the cooling system 1 1 8. The status or level information can then be fed to interface modules 1 31 e and 1 31 f respectively where the information is broadcast to the other interface modules 1 31 in the concrete placement control system 1 30. [0042] Advantageously, coupling the interface modules 1 31 through the communication network 60 allows each interface module to communicate with the other interface module, such that an interface module may determine an operational state of any component associated the concrete placement vehicle 1 0 that is coupled to communication network 60. Further, communication network 60 may be coupled to external networks such as a wireless network to communicate information related to concrete placement vehicle 1 0 to an external computing device. Accordingly, an operator standing outside operator may check information and control systems on vehicle 1 0 from outside operator compartment 1 6. Further, the information may be communicated to a remote computing system for location, maintenance, productivity, and emergency tracking. [0043] The interface modules 1 31 are preferably locally disposed with respect to the respective input and output devices to which each interface module is coupled so as to permit distributed data collection from the plurality of input devices and distributed power distribution to the plurality of output devices. Of course, each of the interface modules 1 31 may, in addition, be coupled to other non-local input devices and output devices. Further, the control system 1 30 can also include input devices and output devices which are not connected to the interface modules 1 31 . [0044] As shown in Fig. 3, the sensors 1 34c-1 34f and the limit switches 1 36c-1 36f are connected as input devices to the interface modules 1 31 c and 1 31 d. The interface modules 1 31 c and 1 31 d thereby receive the sensor information pertaining to concrete mixing motor 1 1 4, delivery system 1 20, water storage system 1 1 6, and cooling system 1 1 8. The actuators 1 32c- 1 32f are connected as output devices to the interface modules 1 31 c and 1 31 d. The interface modules 1 31 c and 1 31 d provide the actuators 1 32 with control signals to change rotation speed for the concrete mixing motor 1 1 4, adjust output from the concrete delivery system 1 20, adjust output from water storage system 1 1 6, and adjusting the cooling level provided by cooling system 1 1 8. The actuators 1 32, the sensors 1 34, and the limit switches 1 36 collectively correspond to the "concrete mixing and delivery I/O devices" which are labeled with the reference numbers 1 40 and 1 42 in Fig. 2. Other I/O devices may also be used. The interface modules 1 31 c and 1 31 d may be located near or on the concrete mixing motor 1 1 4, concrete delivery system 1 20, water storage system 1 1 6, or cooling system 1 1 8 of the concrete placement vehicle 1 0, or, alternatively, the interface modules 1 31 c and 1 31 d may be located anywhere on the concrete placement vehicle 1 0, for example, near where the mixing motor 1 1 4 connects to the concrete placement vehicle 1 0. [0045] The sensors 1 34 may be encoders, resolvers, potentiometers or other suitable measuring devices. The actuators 1 32 may be electrically or hydraulically driven acuators that control the flow of power to the concrete placement vehicle 1 0 and individually to the concrete mixing motor 1 1 4, concrete delivery system 1 20, water storage system 1 1 6, or cooling system 1 1 8. Alternatively, the actuators may be an electric motor. Other arrangements could also be used. [0046] The input devices 1 48 may be switches, knobs, dials, joysticks, etc. According to an exemplary embodiment, at least some of input devices 1 48 are multi-axis joysticks, with the control system 1 30 being capable of receiving operator inputs from either input device 1 48a, 1 48b and using the operator inputs to control the various components of the concrete placement vehicle 10. Preferably, the input devices 1 48 can selectively control the concrete delivery system 1 20. However, it should be understood that the input devices 1 48 may also be configured to control the concrete mixing and its various components such as the concrete mixing motor 1 1 4, the water storage system 1 1 6, etc. [0047] The input devices 1 48 may be configured to control the concrete delivery system 1 20 as follows. For example, the input devices 1 48 may be two-axis joysticks, with left to right corresponding to rotation of delivery chute 1 22 along the semicircular arc and forward and back corresponding to raising and lowering the delivery chute 1 22. Alternatively, input device 1 48 may include a potentiometer such that rotation of input device 1 48 will correlate with rotation of delivery chute 1 22. Additionally, input device 1 48 may include two push buttons, correlating to charging and discharging where each depression of a pushbutton corresponds to increasing and/or decreasing the flow of concrete from mixing drum 1 1 2. Additional or alternative operator input devices may be used depending on what type of operator input is desired. [0048] Because the input devices 1 48 are coupled to the actuators 1 32 through a concrete placement vehicle controller 1 60, the concrete placement vehicle controller 1 60 is a controller configured to process the operator inputs from the input devices 1 48 to provide user-friendly control of the actuators 1 32. For example, the concrete placement vehicle controller 1 60 may be programmed to increase the speed of movement of delivery chute 1 22 as the operator maintains a particular joystick position. For example, if the operator holds the joystick 1 48a or 1 48b in the left position, the speed of lateral movement of the delivery chute 1 22 may be programmed to increase the longer the joystick-left position is maintained. [0049] Referring now to Fig. 4, the arrangement of Figs. 2 and 3 can be used to implement a variety of advantageous features or operations, such as an auto mix operation, a component cushioning feature, interlock control, and other features. Fig. 4 is a functional block diagram of a vehicle controller 1 60 that implements such features. Also shown are the operator interface 144, a concrete placement vehicle controller 1 60, the actuators 1 32, the sensors 1 34, and a plurality of other input devices. [0050] Vehicle controller 1 60 may be implemented using a standalone controller or using one or more interface modules. In the embodiment described herein, the vehicle controller 1 60 is implemented using the interface modules 1 31 c-1 31 f of Figs. 2 and 3. According to this arrangement, all of the interface modules 1 31 are preferably identically programmed, and the interface modules 1 31 each include control programs which implement a plurality of control modules 1 61 including an auto mix module 1 64, interlock control module 1 62, and component cushioning module 1 68. In one example, the interface module 1 31 c receives I/O status information from other interface modules 1 31 through I/O status broadcasts, and maintains an I/O status table based on the I/O status broadcasts and based on locally acquired/determined I/O status information. The interface module 1 31 c then controls the actuators 1 32c by executing those portions of the control programs pertinent to the actuators 1 32c and using the I/O status information stored in its I/O status table. The interface module 1 31 d operates in the same manner, except that it controls the actuators 1 32d by executing those portions of the control programs pertinent to the actuators 1 32d. The interface modules 1 31 a and 1 31 b are not shown in Fig. 4, although it is to be understood that the input information from the operator interfaces 1 44 is received by the interface modules 1 31 a and 1 31 b and transmitted from the interface modules 1 31 a and 1 31 b to the interface modules 1 31 c-1 31 f in the form of an I/O status broadcast over the communication network 60. This configuration is preferred where the control system 1 30 is part of a larger control system that controls all or a large majority of the operations and components of the concrete placement vehicle, as previously described. [0051 ] If the control system 1 30 is dedicated to concrete delivery control, then preferably alternative configurations are employed . For example, the vehicle controller 1 60 may instead be implemented using a single electronic control unit, as previously indicated. [0052] The auto mix module 1 64, interlock control module 1 62, component cushioning module 1 68, and other operations and features will now be described in greater detail. As previously noted, the modules 1 62, 1 64, and 1 68 are preferably implemented as part of the control logic programmed into the interface modules 1 31 a and 1 31 b. 1 . Auto Mix [0053] As shown in Fig. 4, the concrete placement vehicle controller 1 60 has an auto mix module 1 64 that assists the operator in mixing and maintaining a load of concrete. The vehicle controller 1 60 assists the human operator in performing various operations that are part of mixing a concrete load. The vehicle controller 1 60 is capable of repeatedly performing any operation with a degree of precision that a human operator is unable to achieve. Further, the vehicle controller 1 60 is capable of continuously monitoring a concrete load allowing an operator to focus on other tasks such as driving vehicle 1 0 or placing concrete. [0054] As explained above, the concrete placement vehicle 1 0 can be configured to monitor and maintain at least one characteristic of a concrete load independent of operator intervention. In a preferred embodiment, the operator inputs concrete load characteristic information into the vehicle controller 1 60 using one of the operator interfaces 1 44 shown in Fig. 4. The concrete load characteristic information corresponds to at least one characteristic of a concrete load, such as desired slump, moisture content, etc. The concrete load characteristic information is then used by the vehicle controller 1 60 to perform at least one operation in relation to the concrete load characteristic. Exemplary types of operations are discussed further in the following paragraphs. The concrete load characteristic information may be entered in a number of ways and is not to be limited to being entered by the operator. For example, the concrete load characteristic information may be entered by the concrete load producer, a person at the delivery site, or in some other manner. [0055] As shown in Fig. 4, operator inputs are received from one of the operator interfaces 144 and transmitted by the appropriate interface modules 1 31 a or 1 31 b in the form of I/O status broadcasts to all of the interface modules including the interface modules 1 31 c and 1 31 d, which form the concrete placement vehicle controller 1 60. The interface modules 1 31 a and 1 31 b acquire the operator inputs and processes (e.g. scales, amplifies, power conditions, etc.) the inputs to provide to vehicle controller 1 60 to generate control signals to control concrete mixing system 1 1 1 . The operator inputs are provided to the interlock control module 1 62 (the above-mentioned processing may be performed before and/or after the operator inputs are provided to the interlock control module 1 62) . According to an additional embodiment, inputs can be received from both a module and an operator interface where the module is configured to facilitate the operator interface. For example, the module can provide feedback through the operator interface when an interlock is engaged, as described further below. [0056] One of the operations in which the auto mix module 1 64 can assist the human operator is by maintaining a concrete moisture content. By maintaining a moisture content of a concrete load during transportation of the concrete load to a delivery site, the operator is able to deliver the concrete load immediately upon arrival. Further, maintaining a concrete moisture content during delivery from mixing drum 1 1 2 ensures that the concrete load remains uniform during delivery. [0057] Maintaining a moisture content of a concrete load can be accomplished in a number of ways. One exemplary embodiment is depicted in Fig. 5. At step 200, the operator initially inputs a desired moisture content. Alternatively, this desired moisture content may be retrieved from a memory of the controller 1 60, selected from a displayed listing, received from an operator at a delivery site, etc. In addition, to entering desired moisture content input, the operator may alternatively enter other input such as a desired slump factor for the concrete load. [0058] After the desired moisture content is entered or retrieved from memory, the operator can then initiate the auto mix operation as shown at step 202. Preferably, this is done by simply pushing a single button on an operator input device or some other equivalent single input on the part of the operator. However, other ways of initiating the auto mix sequence are within the scope of the disclosed control system. [0059] At step 204, the moisture content of the concrete load is acquired. The moisture content of the concrete load can be obtained by measuring the moisture content of the concrete load using a sensor 1 34 disposed within mixing drum 1 1 2. [0060] At step 208, the moisture content of the concrete load is compared to the desired moisture content input by the operator. If the current moisture content is below the desired moisture content then the concrete load is no longer maintained according to the desired moisture content, and the process proceeds to step 21 6. However, if the current moisture content is above the desired moisture content then the process moves from step 208 to step 21 0. [0061 ] At step 21 0, the rotation speed of the mixing drum 1 1 2 by the mixing motor 1 1 4 and the current engine speed are acquired. A determination is made in a step 21 2 whether the engine speed of concrete placement vehicle 10 is sufficiently high to allow mixing motor 1 1 4 to increase the rotation speed for mixing drum 1 1 2. If sufficient power is available the drum rotation speed can be increased in a step 21 4. Increasing the rotation speed of mixing drum 1 1 2 increases the rate of drying of the concrete load to reduce the moisture content of the concrete load. If sufficient power is not available, a warning indication can be transmitted to the operator at step 220. [0062] If the moisture content is lower than the desired moisture content, water can be automatically added from water storage system 1 1 6 to raise the moisture content of the concrete load to the desired moisture content. In a step 21 6, a controller can determine the current water level in water storage system 1 1 6. If there is sufficient water in the water storage, the controller can control an acuator to begin pumping water from the water storage system 1 1 6 to the mixing drum 1 1 2 to raise the moisture content of the concrete load therein in a step 21 8. Additionally, the controller can increase or decrease the rotation speed imparted by mixing motor 1 1 4 to optimize the integration of the new moisture into the concrete load. If there is insufficient water in water storage system 1 1 6, a warning indication can be transmitted to the operator at step 220. [0063] According to an alternative embodiment, auto mix module 1 64 may be used to implement a timed or count based mixing procedure. An average concrete load can be adequately mixed using approximately 70 rotation of concrete mixing drum 1 1 2. Accordingly, auto mix module 1 64 may be configured to receive a "mix" input instruction from an operator and initiate a process to rotate mixing drum 1 1 2 seventy (70) times. The auto mix module 1 64 may further be configured to vary the rotation speed during the 70 rotations, for examples turning slowly initially do avoid raising concrete dust prior to saturation of the concrete materials with the water. [0064] While Figs. 4 and 5 generally disclose using a feedback control loop to maintain the moisture content of a concrete load, other feedback loops may be implemented with control system 1 30. For example, a feedback loop may be implemented to facilitate delivery of a concrete load from mixing drum 1 1 2 to a delivery point. Another feedback loop may be implemented to "creep" the vehicle 1 0 while discharging. Further, although steps are described sequentially with reference to Fig. 5, the method can include additional or fewer steps and the steps can be performed in any order. 2. Interlock Control [0065] Referring back to Fig. 4, the concrete placement vehicle controller 1 60 has an interlock control module 1 62 that assists the operator by preventing potentially harmful actions from being executed. Examples of some of the many operations performed by the interlock control module 1 62 are given below. [0066] One example of the operation of the interlock control module 1 62 occurs when an operator inputs a desired mixing drum rotation speed that is greater than the drum rotation speed that can be provided based on the power output by the engine of vehicle 10. In a preferred embodiment, the control system 1 30 displays an error message on the operator interface 1 44 informing the operator of the problem. In another instance, the control system 1 30 can be configured to increase the speed for the engine for the concrete placement vehicle 1 0. In still another instance, the control system 1 30 can be configured to increase the drum rotation speed to the rotation speed up to what can be provided based upon the speed for the engine for the concrete placement vehicle 10. [0067] Another example of the operation of the interlock control module 1 62 occurs when an operator delivers concrete from mixing drum 1 1 2. For example, it may be desirable to survey a plurality of additional systems to ensure that safety and operational effectiveness have been maximized. For example, it may not be desirable to allow the mixing drum 1 1 2 to discharge the concrete load while the delivery chute 1 22 is not fully engaged. Another example may include ensuring that the characteristics of the concrete load to be discharged satisfy previously entered characteristics to ensure that a non- conforming concrete load is not delivered. Yet another example may include halting rotation of mixing drum 1 1 2 when it is determined that a concrete load has been fully discharged. [0068] A further example of the operation of the interlock control module 1 62 occurs when components or systems associated with the concrete placement vehicle 1 0 become overheated and need to be cooled. Sensors associated with the overheating system or component that is overheating may detect the condition and activate the cooling system 1 1 8 to begin cooling the system or component. Further, cooling system 1 1 8 may receive the overheat information from the system or component to determine whether the system or component may be cooled while still active based on available cooling capacity, or whether the component should be disengaged. [0069] The interlock control module 1 62 can also be used to prevent other potentially harmful component interactions. For example, it may be desirable to prevent driving of the concrete placement vehicle 1 0 while delivery chute 1 22 is extended. In other instances, it may be desirable to allow driving of vehicle 1 0 while concrete delivery chute 1 22 is extended, for example to allow vehicle 1 0 to creep along while delivering the concrete to spread the concrete, but limit the top driving speed to a maximum value such as five miles per hour. 3. Component Cushioning [0070] Referring back to Fig. 4, the concrete placement vehicle controller 1 60 has a component cushioning module 1 68 that assists the operator by preventing the components of the concrete placement vehicle 1 0 from reaching their mechanical stop points. Typical mechanical stop points include points where a hydraulic cylinder reaches its physical limits or where components physically meet each other or remaining portions of concrete placement vehicle 1 0. [0071 ] The component cushioning module 1 68 constantly monitors the position of various components and ensures that they do not meet their mechanical stop points. For example, during delivery of a concrete load, the component cushioning module 1 68 is given the position of the concrete delivery system 1 20 and its components, namely, the concrete delivery chute 1 22. If the operator has input a position to maneuver the delivery chute 1 22 that is too close to the mechanical stops for the delivery chute 1 22, for example, then the component cushioning module 1 68 will adjust the operator's input accordingly to keep it a specified distance from the mechanical stops. The distance may be set by the operator as an input or may be set by the manufacturer. One exemplary distance is 4 inches from the mechanical stops of a component. However, other distances, such as between 2 and 5 inches will work as well. [0072] As previously noted, the construction and arrangement of the various aspects of vehicle 1 0 and the control system 1 30 shown in the preferred and other exemplary embodiments are illustrative only. The components disclosed in the figures are shown only by way of example and should not be construed to limit the applicability of the present disclosure to controlling only those components. Although only a few embodiments of the present inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible without materially departing from the novel teachings and advantages of the subject matter recited in the claims. Accordingly, all such modifications are intended to be included within the scope of the present invention as defined in the appended claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the preferred and other exemplary embodiments without departing from the scope of the present inventions as expressed in the appended claims.