Construction of a cyclogram for a machine module; calculation of cycle performance and its load factor. Calculation of parameters and construction of a cyclogram of a rhythmic flow Group preventive lesson
A cyclogram is a graph that reflects the sequence of movements of all elements, mechanisms and devices included in the machine tool system. On the horizontal axis, time is plotted on a certain scale, and on the vertical axis, a list of designations of the elements involved in the work, i.e., moving, spending some time, is given. The purpose of the construction is to obtain the value of the duration of the operating cycle (T C) of the equipment (in our case, the entire ACM) for the subsequent determination of the performance of the module, as well as the possibility of optimizing the cycle by reducing the time spent on transitions.
It reflects the sequence of operation of all mechanisms (elements) of the module within the time of the complete processing cycle of the part. To construct a cyclogram, it is necessary to know the speeds of angular and linear movements of the executive bodies of an industrial robot, as well as their values in accordance with the developed layout.
On fig. 2.74 shows the cyclogram of AFM operation using MP20.40.01 model PR, equipped with a mechanical gripper (grip). Before constructing a cyclogram, a table is drawn up, which indicates the nature of the movements, the number of the cycle and the time of its execution according to the program given to the robot. The operating time of the CNC machine can be indicated as a general segment, without splitting into separate technological transitions, since it is known and calculated in the technological part of the project. It is most convenient to set the time in seconds (s). The calculation and construction of time intervals should be carried out with sufficient accuracy equal to 0.1 s.
The time intervals themselves are plotted on the horizontal axis of the graph and are determined for each transition by calculation. In this case, it is enough to know the speed of movement (it is known from its technical characteristics) and the amount of movement (size), which is set constructively within the limits of possible movements for the robot of the selected model.
The time for “clamping-unclamping” of the gripping device (grip), which is difficult to calculate, can be taken approximately up to 1 s. It is necessary to provide auxiliary time for the installation and fixing of the part by the worker-operator in case of its use in non-automated versions of machine modules.
In table. 2.13 shows the content of technological transitions performed by the elements of the GPM and the time spent on their implementation.
Tab. 2.13. The content of technological transitions performed by ACM elements
| cycle number | Content of executable commands | Cycle time, s |
| t1 | Lowering the robot arm vertically down by 0.1 m | 0,5 |
| t2 | ||
| t3 | Rotate the arm 90º and simultaneously rotate the hand 90º counterclockwise | 1,5 |
| t4 | 1,5 | |
| t5 | Movement of the counter spindle of the machine to the left and clamping the workpiece with the jaws of a mechanized chuck | 1,5 |
| t6 | Operation of the PR gripper on the "unclamp" | |
| t7 | 1,5 | |
| t8 | Extension of the arm in the horizontal direction forward along the OX axis by 0.79 m | 1,5 |
| t9 | Operation of the gripper on the "clamp" | |
| t 10 | Opening the jaws of a mechanized chuck | |
| t 11 | Retraction of the arm in the horizontal direction along the OX axis back by 0.79 m | 1,5 |
| t 12 | Rotate the arm 135º and simultaneously rotate the hand counterclockwise 90º | 2,25 |
| t 13 | Operation of the gripper on the "unclamp" | |
| t 14 | Turning the PR arm by 45º and simultaneously raising the arm vertically by 0.1 m | 0,75 |
After building a network diagram and determining its time parameters, a check is made for the compliance of the obtained terms with the duration of development with normative or directive terms. Next, the structure of the network model is analyzed, revealing the heterogeneity of the intensity of the project work.
At present, in practice, the network model is first corrected in time, i.e., it is brought to a given project completion date. Then they proceed to adjust the schedule according to the criterion of resource allocation, starting with labor resources.
Minimizing the number of project executors while maintaining its execution time
In the course of performing a complex of works, the employment of workers of various qualifications and different specialties turns out to be uneven. This leads to an overestimation of the need for them with a simultaneous decrease in the average level of employment and, as a result, to overspending of wages and an increase in the cost of the entire project.Most often, in practice, it is necessary to optimize the network schedule with a limited resource of performers of a certain category. Optimization by the number of performers is based on the shift of work within the limits of their available time reserves. Its goal is to ensure the most even employment of workers throughout the duration of the project while maintaining the overall duration of the project.
To carry out such optimization, a simple and intuitive graphical method is often used. According to the network model, line chart (tie chart) and project map (download schedule).
On the line chart, the works are marked on the y-axis, placing them from bottom to top in ascending index. A uniform time scale is applied to the abscissa axis (usually in days). Each work is drawn to scale by a straight line segment, the length of which is equal to the duration of the work.
Critical path activities are highlighted with double lines. Under the arrow depicting the work, the number of employees of each category engaged in the performance of this work is placed in the form of a hanging flag. In the original diagram, all jobs start at their early dates, and the dummy job is indicated by a dot.
Checking the correctness of building a line chart is the end date of the last work of the project, which coincides with the duration of the critical path. The practical value of the anchoring schedule is that it can be used to improve the efficiency of the use of the labor resource.
The project map (loading schedule, schedule of daily needs of workers of the relevant categories) for ease of construction and analysis is built under the line diagram. For each day, the total number of performers employed in parallel project activities is determined and plotted on the scale along the y-axis. At the same time, a part of the performers employed on the critical path works is highlighted with a dotted line and hatching. Each category of performers has its own project map. The following is an analysis of their employment.
Optimization of the workforce resource consists in the simultaneous solution of two problems:
- minimize the number of simultaneously employed performers;
- equalize the need for labor resources throughout the entire duration of the project.
- moving jobs along the time axis can only be done to the right (postponing their start);
- the work of the critical path cannot be touched, because this will lead to an increase in the duration of the entire project;
- jobs that have a free time reserve can be easily moved by the amount of this reserve;
- moving jobs that have only full slack requires a similar shift of subsequent jobs;
- moved works on a line diagram are highlighted by marking with a noticeable symbol: an asterisk, a stroke, a color, etc.
Optimization is carried out in stages, starting with the areas of the highest and lowest employment of performers. All line diagrams and maps of the project are displayed in the same way as the original ones. The number of optimization stages depends on the complexity of the project and the skill of the spotter.
Let's consider a graphical method using the example of network graph optimization presented in Table. 1 and fig.1. Optimization is carried out using a calculator. It must be optimized by the number of performers (for simplicity, one category of performers is adopted in the example).
According to the recommendations, we will draw up a line diagram and a project map (a schedule of daily resource requirements) and conduct a preliminary analysis of the employment of performers (Fig. 2). According to the daily demand schedule, it can be seen that on different days of the project implementation there are different employment of performers: first they need 5 (1-4 days), then 15 (5-10 days), then only 3 (16-18 days), again 8 ( 20-28 days), again 3 (29-30 days) and finally 6 (31-34 days). Thus, we have a clear uneven employment of performers (sometimes overloaded, sometimes underloaded with work).
Table 1
| Work ( ij) | Duration t(ij), days | Number of performers |
| 1,2 | 4 | 5 |
| 2,3 | 6 | 3 |
| 2,4 | 5 | 6 |
| 2,7 | 11 | 6 |
| 3,5 | 9 | 1 |
| 4,6 | 9 | 2 |
| 5,7 | 11 | 3 |
| 6,7 | 10 | 5 |
| 7,8 | 4 | 6 |
Rice. 1. Network diagram example
Let's carry out a more detailed analysis of the line chart and project map in order to optimize labor resources: by equalizing the need for them throughout the project and minimizing the number of simultaneously employed performers. The daily resource requirement graph shows that the minimum number of performers cannot be less than 6 people, which is determined by their need for critical path activities. A 15 performers in the 5-10 days project area is clearly overpriced and subject to correction in the first place.
Rice. 2. Line diagram and project map before optimization
15 performers are busy at work 2,3; 2,4 and 2,7 . work 2,3 cannot be touched, because this is the work of the critical path. Work 2,4 has only full reserve, but no free time reserve. Work 2,7 has a solid free time reserve and is therefore the most preferable for optimization. Use part of the free reserve by moving work 2, 7 (5-15 days) for 5 days (her new term is 10-20 days). Thus, the maximum required number of performers was reduced to 9 people, i.e. the task of minimizing the labor resources of the project can be accepted as completed.
Rice. 3. Line diagram and project map after optimization
Next, we will solve the problem of equalizing the need for resources by analyzing the time intervals associated with the "failures" of the project map. Taking into account the movement of work 2,7
there will be no drop in demand for contractors in the middle of the project (16-18 days), but it will remain closer to the end of the project (29-30 days). To smooth out the load schedule, move the work 6,7
(19-28 days), having a free time reserve, for 2 days (new term 21-30 days). Also, in order to equalize the need for labor resources, we will move work 4,6
(10-18 days) for 1 day (11-19 days).
As a result of optimization, we arrive at a line diagram and a project map shown in Fig. 3. The graph shows an improvement in the uniformity of the workload of performers: the new daily resource requirement is from 5 to 9 people, depending on the stage of the project, there are no sharp fluctuations in employment. At the same time, the duration of the entire project remained unchanged (34 days), i.e., the necessary optimization condition is met.
The strategy of the minimum increase in the cost of the complex of works while reducing the time
Organization of the construction flow, consisting of n private streams or brigades passing through N grips, is based on the calculation of its parameters, which include the rhythm of the teams or the cyclicity module (t br), the flow step (t w) and the intensity or power of the flow (Y).
By the rhythm of the brigade(modulus of cyclicity) is the duration of the work cycle performed by the brigade on one grip.
Pitch flow called the length of time after which the finished product is obtained from the stream. It can be a building, structure, its finished part or section, etc.
flow rate called the volume of products produced by one or more teams per unit of time.
The entire construction flow, as a rule, consists of three periods in time: the development of the flow (t razv), the time of operation of the steady flow (t set) and the time of the clotting of the flow (t sv). Rice. 2.2. It should be noted that the most efficient are long-running streams. In this case, the periods of development of the flow and the time of its clotting are infinitely small compared to the steady-state time of work. Under these conditions, the operating teams constantly produce homogeneous products of a certain volume. In this case, such a calculated parameter as the average number of workers or the average value of resources (R) is of great importance, in contrast to their maximum number (R max).
Rice. 2.2. Basic flow parameters
The degree of fluctuation in the number of workers or resources in general, participating in production during the construction process, is measured by the coefficient of unevenness a. It can be defined like this:
where V i - the volume of the corresponding type of work; H vr - the norm of time; T is the total duration of the work.
The duration of work on one grip is:
At the same time n i =
where n i is the number of workers who, according to the condition of work, should be employed on the grip, F is the total front of work on the grip, f is the front of work per worker or link.
Rice. 2.3. Graph and cyclogram of rhythmic flow.
Under these conditions, when the rhythm of the brigade or the step of the stream can be determined, the total duration of the erection of the object can be determined as follows:
Т = n t w + (N - l)t w = (n + N - l)t w (2.1.)
or. T \u003d T 1 + (N - l) t w. (2.2.)
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In this case, T 1 is the duration of all work on the grip; n is the number of teams in the stream; N is the number of traps in the stream, which can be defined as
where å t br = T 1, åt z - duration of technological and organizational breaks.
The general flow diagram with a constant rhythm is shown in fig. 2.3.
During the construction of a multi-storey building, in the case of organizing several tiers within a storey, the total duration of construction can be determined as follows:
T \u003d T 1 + (N E - l)t w (2.4.)
where E is the number of tiers.
As can be seen from this, the duration of the work depends on the number of grips, the number of teams in the stream and the step of the stream. In this case, the number of captures can be reduced by concentrating a larger number of processes on one capture.
For a given, total construction time, for preliminary calculations, the flow step can be defined as
A decrease in the flow step leads to the most complete combination of the work of the team in time and a reduction in the period of work. Thus, for a given construction duration and the accepted flow step, the number of captures can be determined as
Rhythmic flow is characterized by the ratio t w = t p , i.e. the step of the flow is equal to the rhythm of the work of the teams (links), on the basis of which, according to the above formula, the total time for performing work at the facility is determined.
T o \u003d t w * (n b p - N capture -1), (2)
where: T o - total execution time of the thread, days;
n br - the number of teams, due to the given number of specialized works at the facility and the number of installed erection cranes.
The number of links at the facility in one shift is determined by the scope of work:
N star cm \u003d F about / f star * K tb, (3)
Where: F about - the front of work at the facility (per floor or one mark), m 3, m 2, m, span;
f star - the scope of work according to the calculation for the operation of the link, m 3, m 2, m, span;
K tb - safety factor according to the conditions of safe work (K tb \u003d 1.3-1.5).
The number of workers at the facility in one shift is determined by multiplying the number of links by the number of workers in the link
n slave \u003d n sv cm * n slave sv (4)
When calculating, it is assumed that for one assembly (tower) crane per shift, one link of installers, numbering 4-6 people, should be planned, and the link of masons is taken depending on the thickness of the wall and the complexity of the masonry, numbering 2-3 people. The team of masons includes 6-8 links, and the team of installers - 2-3 links.
Examples of constructing cyclograms of rhythmic flows are shown in fig. 2.3.
Calculation of parameters and construction of a cyclogram
Unrhythmic flow
The calculation of the parameters of non-rhythmic flows and their linking with each other can be carried out by a graphical, analytical or matrix method.
The most algorithmic is the matrix method, which allows in a specific form to obtain all the necessary data for constructing cyclograms.
Usually, as a result of the calculation, the following are determined:
Dates of beginning (t jj n) and completion (t jj o) of the work of each team (link) on the grips (I - the number of the grip; j - the number of the process);
The total duration of the in-line execution of all work (T o);
The amount of downtime of the front of work on each grip.
The most detailed method involves dividing the entire calculation process into three stages.
At the first stage the initial matrix is drawn with the conditional start of all processes on the 1st grip from the zero point, i.e. t jj n =0. This is necessary to determine the magnitude of the shift in the beginning of subsequent work, subject to the continuity of the work of the teams.
In the upper left part of each cell of the matrix, the beginning of the process on the grip (t jj o) is indicated, in the middle - the duration of the process (t jj), and in the lower right part - the end of the process on the grip
(t jj o = t jj n + t jj) (5)
The filling of the primary matrix is performed by columns (processes) from top to bottom (see Table 1).
Table 1 - An example of calculating a non-rhythmic flow (first stage)
At the second stage of for each grip, the possibility of starting a subsequent process on it, taking into account the end of the previous one, is determined. We carry out the calculation line by line (I, II, etc. captures), and write the result in a circle at the junction of two processes. For example, foundations can be started on the 1st grip only after excavation is completed, i.e. on I - and day, not 0 - and, installation of the frame - on the 10th day, installation of the roof on the 12th day, installation of equipment on the 5th and finishing work - on the 10th day. We make similar calculations for the rest of the grips, based on the condition t i (j +1) n = t ij o.
Then, for each column (process) below, we write out the maximum value of the shift in the work of this grip, based on the condition for the continuity of the work of the teams (see Table 1).
On the third stage the final matrix is filled (Table 2), in which the beginning of each technological process is shifted by an amount equal to the sum of the previous shifts (for example, finishing work must be started in 1-10 + 38 + 5 = 90 days), and the full characteristics of the flow are determined:
The value of the total shift of the beginning of the flow t ij shift =∑t i (j -1) shift
Beginning of processes t ij n = t ij pr + t ij shift
End of processes t Nj o = t Nj n + t Nj
The total duration of the processes ∑t ij = t Nj o - t ij n
The total duration of the in-line execution of work T about =∑ t ij +∑ t ij shift
Downtime of the prepared front of work on the grips t i pr \u003d∑ n i \u003d 1 (t (j -1) n - t ij o)
The total amount of idle work front ∑ i =1 N t pr
The density coefficient of the work schedule K pl \u003d ∑t ij / ∑t ij + ∑t ij pr
Table 2 - An example of calculating a non-rhythmic flow (second stage)
Based on the calculated parameters obtained, a cyclogram of a non-rhythmic flow is constructed (see Fig. 4).
In accordance with Min. Education and Science dated March 27, 2006 No. 69 "On the peculiarities of the working hours and rest time of pedagogical and other employees of educational institutions" (see Appendix 2 ) and a document on the approximate distribution of the working time of a teacher-psychologist (see Appendix 5) we have developed a recommended cyclogram of work and derived approximate norms of work in various areas during the week.
Approximate distribution of working hours
teacher - psychologist of the preschool educational institution during the week (rate).
Approximately per week:
work with children - 11h
work with teachers - 3.5 hours
work with parents - 3.5 hours
Notes:
1. It is advisable to place the cyclogram on 1 A4 sheet and hang it on a stand or office door so that you can see what the psychologist is doing at the moment.
2. The cyclogram is certified by the head of the preschool educational institution and the head of the GMO of pedagogues-psychologists of the preschool educational institution of the city.
Option 1. Cyclogram of the work of a teacher-psychologist MDOU No. ___.
| Days and hours | Work with children | Working with parents and teachers | methodical time | |
| Monday | 7.30 -8.00 | Preparation for the individual classes | ||
| 8.00-11.30 | Individual sessions | |||
| 11.30-12.30 | Diagnostics on demand and plan | |||
| 12.30-14.30 | Paperwork | |||
| Tuesday | 7.30 – 8.00 | Individual consultations | ||
| 8.00-8.30 | Emotion-vol. sphere | Groups of correctional development. lessons | ||
| 8.30- 9.00 | Intel. sphere | |||
| 9.00-9.30 | Aggression, anxiety | |||
| 9.30-10.00 | Current | |||
| 10.00- 12.00 | Scheduled Diagnostics | |||
| 12.00 -13.30 | ||||
| 13.30-15.30 | Education and correctional and developmental work (group forms of work) | |||
| Wednesday | 9.00-14.00 14.00-14.30 14.30-16.00 | Compilation of ind. development programs, preparation of diagnostic materials, preparation of group classes with teachers, parents (trainings, seminars, consultations, discussions) Drawing up leaflets and posters for psychoeducation Visits (library, seminars, classes), practical work to develop the educational and methodological base of the cabinet. | ||
| Thursday | 10.00-13.00 | Weekly Diagnostic Processing | ||
| 13.00–15.00 | Registration of current documentation | |||
| 15.00-16.00 | GKP (preparation for school) or individual busy. | |||
| 16.00 -17.00 | Individual consultations and group forms of work | |||
| Friday | 7.30-8.00 | Preparing for the group and ind. classes | ||
| 8.00-8.30 | Junior gr. | Group preventive classes | ||
| 8.30-9.00 | Average gr. | |||
| 9.00-9.30 | Senior gr. | |||
| 9.30-10.00 | Will prepare. gr. | |||
| 10.00-11.30 | Individual sessions | |||
| 11.30-13.00 | Individual consultations | |||
| 13.00-14.30 | Registration of current documentation |
Total: 18 hours - organizational and methodological work,
18 hours - diagnostic, corrective, preventive and advisory work.
Option 2
(Medical-psychological-pedagogical diagnostic service in the preschool educational institution / edited by E.A. Karalashvili, Supplement to the journal "Management of the preschool educational institution, 2006).
Cyclogram of the work of a teacher-psychologist MDOU No. ___.
Monday
Individual diagnostic, corrective work
Group preventive work. Senior group
Individual diagnostic, corrective
Work
Working with teachers
13.00 - 14.00 - analysis and generalization of the results
14.00 - 15.30 - preparation for consultations with parents
Tuesday
8.00 - 8.30 - preparation for classes
Individual consultations with parents
Subgroup psychoprophylactic lesson. preparatory group
9.30 - 10.30 - individual diagnostic, corrective work
10.30 - 12.30 - individual in-depth diagnostics of emotional and
cognitive sphere
Participation in psychological and pedagogical consultations of an educational institution
13.30 - 14.00 - processing of the results
14.00 - 15.30 - preparation for individual-group work
Wednesday
9.00 - 13.00 - attending district meetings, seminars, lectures
13.00 - 18.00 - analysis of psychological and pedagogical literature *
Thursday
8.00 - 8.30 - preparation for classes
Individual consultations with parents
9.30 - 10.50 - individual diagnostic, corrective work
Group psychoprophylactic lesson. Second junior group
Individual work with parents
13.00-14.00 - processing of the results
14.00-15.00 - preparation for individual work with teachers
15.00 - 16.00 - filling out reporting documentation
Friday
13.00 - 13.30 - preparation for consultation work with parents
Working with teachers
Subgroup psychoprophylactic lesson.
preparatory group
