Background technology
The laser controlled leveling technology is technological as state-of-the-art in the world land readjustment at present, has obtained using widely in developed countries such as America and Europe, Japan in recent decades.Laser leveling system is mainly shoveled etc. by generating laser, laser pickoff, controller, hydraulic system pacifically to be formed.Laser pickoff is the key components of laser leveling system.Laser pickoff is to receive transposition by the signal that the photoelectric sensor that a series of vertical symmetry with control point, center distribute constitutes.Laser pickoff is vertically mounted on the level land and produces on the mast of equipment; Bridge as transmitter that connects that excuse me and controller; Receive laser signal in real time, thereby confirm the instantaneous position deviation at laser reference plane and control point, center, and send corrected signal to controller from generating laser; Up-down by controller control Leveling implements is positioned within the laser reference plane control point, center of receiver.Laser pickoff mainly is made up of optical system, photodetector, low-noise amplifier, shaping and widening circuit etc.; Be mainly used in opto-electronic conversion and the transmission of completion to laser pulse signal, its comprehensive technical indexes is mainly determined by the performance indications of detector and amplifier.
The laser leveling system general work is in the wild environment of complicacy; When ambient light was shone by force, light intensity adaptability was relatively poor to external world for present laser pickoff circuit, the circuit saturated phenomenon often occurs; Cause system's cisco unity malfunction; Need just to carry out work after artificially light intensity or circuit parameter are intervened to external world, this just makes that the operating efficiency of system and work quality are seriously influenced.
Summary of the invention
The technical problem that (one) will solve
The technical problem that the present invention will solve is: how to improve the laser controlled leveling acceptor circuit adaptability of light intensity to external world, the stability and the automaticity of laser controlled leveling acceptor circuit place laser leveling system are improved.
(2) technical scheme
In order to solve the problems of the technologies described above, the present invention provides a kind of laser controlled leveling acceptor circuit, and it comprises:
The multi-path laser testing circuit is used for converting optical signal into the logic gates data signal;
Gain Automatic adjustment circuit links to each other with said multi-path laser testing circuit, is used for regulating automatically according to extraneous light intensity the gain of said multi-path laser testing circuit.
In the above-mentioned laser controlled leveling acceptor circuit, each the road laser sensor circuit in the said multi-path laser testing circuit comprises:
Optical-electrical converter is used for converting optical signal into the signal of telecommunication;
Preamplifier and main amplifier, said preamplifier links to each other with said optical-electrical converter, and said main amplifier links to each other with said preamplifier, is used to amplify the said signal of telecommunication;
Shaping circuit and widening circuit, said shaping circuit links to each other with said main amplifier, and said widening circuit links to each other with said shaping circuit, and being used for the electrical signal conversion after the said amplification is the logic gates data signal.
In the above-mentioned laser controlled leveling acceptor circuit, said Gain Automatic adjustment circuit comprises:
Optical-electrical converter is used for converting external optical signals into current signal;
Amplifier links to each other with said optical-electrical converter, said current signal is amplified and converts voltage signal into export;
Comparator links to each other with said amplifier, also is connected with reference voltage on it, the voltage signal of more said reference voltage of comparator and amplifier output, output height/low level;
Analog switch links to each other respectively with said preamplifier with said comparator;
Gain-adjusted resistance links to each other respectively with said preamplifier with said analog switch.
In the above-mentioned laser controlled leveling acceptor circuit, said Gain Automatic adjustment circuit comprises the said analog switch of multi-channel parallel, and the analog switch of said multi-channel parallel links to each other with said comparator respectively.
In the above-mentioned laser controlled leveling acceptor circuit, the way of said analog switch is identical with the way of said laser sensor circuit.
In the above-mentioned laser controlled leveling acceptor circuit, the way of said gain-adjusted resistance is identical with the way of said analog switch.
In the above-mentioned laser controlled leveling acceptor circuit, said comparator is set to one or more parallel connection.
In the above-mentioned laser controlled leveling acceptor circuit, in the comparator of said multi-channel parallel, an end of each road comparator links to each other with said amplifier, and the other end links to each other with said analog switch.
In the above-mentioned laser controlled leveling acceptor circuit, the reference voltage that the comparator of said multi-channel parallel connects is different.
In the above-mentioned laser controlled leveling acceptor circuit, in the reference voltage that the comparator of said multi-channel parallel connects, when Vi>Vj; Ri<Rj, wherein, Vi, Vj are respectively the reference voltage of the two-way comparator connection of parallel connection; Ri, Rj are respectively and reference voltage V i, the corresponding gain-adjusted resistance of Vj, 1≤i≤n, 1≤j≤n; And i ≠ j, n are the way of the comparator of parallel connection.
(3) beneficial effect
Compare with existing laser controlled leveling acceptor circuit; Increased the functional module that to adjust gain amplifier according to extraneous light intensity automatically in the laser controlled leveling acceptor circuit of the present invention; Strengthened the adaptability of system for extraneous light intensity; Improve the stability and the automaticity of system, be applied in the land readjustment, made land readjustment efficient and smooth precision be improved.
Embodiment
Below in conjunction with accompanying drawing and embodiment, specific embodiments of the invention describes in further detail.Following examples are used to explain the present invention, but are not used for limiting scope of the present invention.
Laser controlled leveling acceptor circuit of the present invention comprises multi-path laser testing circuit and Gain Automatic adjustment circuit.
Laser sensor circuit is as shown in Figure 1, comprises optical-electrical converter, preposition amplification appliance, main amplifier, shaping circuit and widening circuit.At first; Incident light is through the influence of combination filtering apparatus with the weakening bias light; Convert optical signal into the faint signal of telecommunication through opto-electronic conversion then; Realize the amplification of small-signal again through preamplifier and main amplifier, (Transistor-Transistor Logic, TTL) data signal sends controller to convert pulse signal into logic gates through shaping and widening circuit at last.
Gain Automatic adjustment circuit is as shown in Figure 2, comprises optical-electrical converter, amplifier, comparator, analog switch and gain-adjusted resistance.Optical-electrical converter is used to detect external optical signals and converts current signal into; Amplifier amplifies current signal; And the voltage signal that converts certain amplitude into is exported; This voltage signal input comparator and positive reference voltage compare, and the high-low level of comparator output is used to control the break-make of analog switch, decide gain-adjusted resistance whether with the preamplifier of above-mentioned multi-path laser testing circuit in feedback resistance parallelly connected; Thereby realize the automatic adjusting of feedback resistance size, the automatic adjusting of gain amplifier just.When extraneous light intensity surpassed certain intensity, the output voltage of amplifier was during greater than reference voltage, comparator output high level; Analog switch is closed; Gain-adjusted resistance is parallelly connected with the feedback resistance of preamplifier, causes the feedback resistance of preamplifier to diminish, and gain diminishes; Otherwise, the comparator output low level, the control analog switch breaks off, and keeps the feedback resistance size of preamplifier constant, and gain remains unchanged.When ambient light was shone by force, the pregain of laser pickoff can diminish automatically, has prevented the saturated of amplifier, has guaranteed system stability work.At the output of comparator, according to analog switch and the gain-adjusted resistance of the identical way of the way of laser sensor circuit parallel connection, with the automatic adjusting that realizes that all laser sensor circuits gain.
Be to improve degree of regulation, can be at the comparator of the different reference voltages of output parallel connection of amplifier, the output of every road comparator; According to analog switch and the gain-adjusted resistance of the identical way of the way of laser sensor circuit parallel connection, the resistance of gain-adjusted resistance reduces along with the increase of front end reference voltage, i.e. in the reference voltage of the comparator of multi-channel parallel connection; When Vi>Vj, Ri<Rj, wherein; Vi, Vj are respectively the reference voltage of the two-way comparator connection of parallel connection, and Ri, Rj are respectively and reference voltage V i, the corresponding gain-adjusted resistance of Vj, 1≤i≤n; 1≤j≤n, and i ≠ j, n are the way of the comparator of parallel connection; Thereby guarantee the enhancing along with the ambient light line strength, circuit gain descends gradually.
The above only is a preferred implementation of the present invention; Should be pointed out that for those skilled in the art, under the prerequisite that does not break away from know-why of the present invention; Can also make some improvement and replacement, these improvement and replacement also should be regarded as protection scope of the present invention.