3D Finishing 1

What do you understand by the 3D finish process?

• 3D finish is the process where the design is being completely finished & to be ready for final simulation & 2D detailing.
• While finishing the design the nominality of holes is checked which ensures the easy assembly of all the units.
• The hole concentricity & holes sizes are checked which ensures the easy assembly of different parts.
• The gaps between the different units are used to ensure the proper in working units.
• Fasteners are implemented as per the hole size & the standard color codes as per the customer requirements are applied to differentiate the type of hole
• whether it’s a simple hole, threaded hole, or counterbore hole.
• Renaming the assembly & the part is done to give every part a different identity. So everyone can identify in which assembly the particular part is going to be fit.
• After doing all these things the model is sent to the simulation department to Simulate the design with robots whether the gun is clashing or not & 2D detailing.

What are the points that need to be taken care of while finishing the design?

The following points are taken into consideration while finishing the design.
1. PANEL DATA
2. WELDING & RIVET POINTS
3. PPSL PURCHASE PART SOURCE LIST
4. PLP – PRINCIPLE LOCATING POINT
5. START FROM NC- NUMERICAL CONTROL
6. BASE MOUNTING POSITION VALUE
7. BUY OFF SHEET
8. COLOUR CODE DATA

PANEL DATA:

• Panel knowledge
• Check misassemblies in the panel
• Number of panels

WELDING & RIVET DATA:

• 
  Get welding & rivet data from costumer
• Welding & rivet operation process

PROCESS FOR DESIGN:

• 
  The sketch should be fully constrained
• The gas cut profile should be in thickness face with edge fillet
• 3mm radius for < 50mm thickness
• 5mm radius for > 50mm thickness
• using 5mm radius for 20mm plate it will remove material is large than 3mm
• Rough machining
• Fine machining
• Maintain 3mm machining step
• Clearance 3mm between shim and machining step.
• In some case, 2mm and 2.5mm machining step can use.
• edge fillet 5mm, it depends upon tool diameter.
• Avoid unnecessary fine machining
• Holes

NC - NUMERICAL CONTROL:

• 
  Start from NC.
• The Nc charping surface should cover 16mm diameter of plug point.
• Nc should be in absolute and have a round-off value in x,y, z-direction.
• Nc clamping should be on a plain surface (no bend, curved surface), if two or three panels are there, having the same plp the clamping surface must be common for both panels.
• Maintain minimum clearance 15mm between nc(make parts) to panel and weld points.
• Maintain clearance 10mm in special case 5mm.
• Mention non-magnetic stainless steel note if welding point is very close to nc.
• The length of NC is small in size to avoid vibration.

MAKE PART:

• 
  Overall length should not be in 0.5 value both horizontal & vertical like 95.5
• add rib if required to avoid overhanging
• design weldment in the part body or product depending upon no. Of parts.
• welding clearance.
• weldment clearance minimum 5mm.

GENERAL CHECKLIST:

• 
  The unit should be in absolute in tool vise
• All NC should be in absolute
• Nc face should be round off except angle NC (round off in one side)
• Gas cut profile there should be there.
• The thickness face machining step depends on stock size
• Nc dowel should be in slip fit e8 and mounting part should have press-fit
• Riser base mounting in slip fit e8
• The hole should be inline
• Check clash analysis
• Colour code
• Check 3d properties

What are the rough locators & what is their use?

• A rough locator is a part designed to guide the operator, to locate the car panel onto the pins accordingly. A rough locator can be of standard part or make the part.
• Rough locators are used to help locate workpieces in the automation process. Locating refers to the desired location where we want the workpiece to be sitting. when it is getting on either worked on either by a person, team, or a robot.
• Body part rough locators are provided to assist manual part loading to the tool.

The following are general guidelines for rough locators:

• 
  It is not required to finish cold/hot rolled steel for rough locator mounting. Use NAAMS standard rough locators when possible.
• If possible, do not place rough locators in positions that force the operator to lift and load, or unload the part over the rough locators.
• Rough locators must be designed with slots for ease of adjustment.
• Rough locators should have minimal part contact so that the operator can load the part to the work location with ease. Excessive part contact may cause difficult part loading and unloading.
• Rough locators must never touch the part when it is nested or controlled by the primary tool locators.
• If the rough locator requires a unique design, use the design parameters for the standard NAAMS rough locator as a guide.
• A rough locator is a part designed to guide the operator, to locate the car panel onto the pins accordingly. A rough locator can be a standard part o make the part.
• It is used to identify the correct orientation of the panel.
• It can be called a foolproofing method also. Because due to the rough locator the part cannot be loaded in the incorrect position. The rough locators are set according to the angle of the respective panel hence parts can only be loaded in a defined orientation.

What are the points you need to consider while designing a rough locator?

Following are the points that need to be considered while designing the rough locator:

• 
  Rough locators should be placed at the edges of the car panel, which it has to guide.
• Rough locators have to be placed at the same angle of the car part edge with a minimum distance of 2-5 mm from the edge of the car panel.
• Rough locators should guide the panel in a pin arresting direction.
• Rough locators should start guiding the panel before 10 to15mm to the start of the pin engagement.
• Rough locators should be designed with an entry angle for the car panel. Generally, it ranges between 30-45 degrees.
• Rough locators should be designed with two slots to mount the easy adjustments.
• The slots should be in the direction of car part guiding.
• Rough locators must be designed with slots for ease of adjustment.
• Rough locators should have minimal part contact so that the operator can load the part to work location with ease. Excessive part contact may cause difficult part loading and unloading.
• Rough locators must never touch the part when it is nested or controlled by the primary tool locators

What is the gun study process?

• Welding is mostly used in automobile industries and their requirements for fixtures that ease the welding process is a continuous developments task in any industry.
• In the weld study process, the major procedure is inserting the gun in the tool assembly and placing the gun on the weld spots by creating a point on the tip. Adjust the weld gun for not to get any clashes from the 3D concept.
• Once all the weld spots are cleared without any clashes and it will be moved on to the next procedure of simulation.
• In the simulation, first, we have to check with the reach with respect to the weld spots. Because robots are also having some limitations if it exceeds the robot will not work properly with 100 percent. So first we have moved with reach check and then try to adjust the weld gun with respect to 3D concept design. If any clashes get in simulation, we will get cleared with CATIA software.
• Car Body In White (BIW) is a complicated steel structure including 300-500 sheets with complex shapes and are assembled by means of welding in a high rhythm through 55-75 robotic workstations.
• The foremost step taken before starting the welding fixture design, we must declare weld spots location for each and every panel. The location and orientation of other critical units of the fixture including clamps, locators., etc are decided based on the weld spot distribution.

Now coming to the point, in weld study, first we have to choose which gun has to be used for the welding process. Gun has two different types, they are
1. C – Type gun.
2. X – Type gun.

C – Type gun:
In C – type gun one arm side is fixed and another arm is movable in a linear direction of perpendicular to another arm (Horizontal direction with respect to another arm).

X – Type gun:
In X – type gun one arm side is fixed and another arm is movable in angle position (it moves like an arc).
It includes the study of the weld matrix & the weld point positions. There are two types of weld points one is Geo weld which ensures the geometry of the assembly & the second is Re-spot weld points which add strength to the welded parts.

The fixture is designed for the car panel to hold it in the position, so we ensure all the weld spots and weld gun do not cross or any clash with the fixture tool.

If any clashes are defined while designing fixtures, then we will only move on to redesign the tool. We have no permission to change a weld spot or clamping
position without considering clients.

What are the points that need to consider during the gun study?

Weld gun study is a very time-consuming process, the entire welding cycle time study depends on the no. of spots & the weld gun study.

Following are the points that need to consider during the gun study.

The axis of the weld spot along the welding direction must be normal to the weld surface.

The no. of weld spots for the panel the time required to spot each weld & the total time required to complete all the weld spots.

We have only access to rotate the weld gun on Z-axis. Because if we rotate the weld gun on X and Y axis the weld spot quality will reduce and the precision will get lost.

During the gun study, we have to consider the client's cycle time and we have to maintain the cycle time compared to clients' requirements. There are two types of weld spots they are,

geo spot and respot and these two spots are having different timings.

Geo spot – 3sec.

Respot – 2.5sec.

If we have one or more device models and we want to program, the behavior of each model in the work cell can be simulated over time. Instruction for each device is coded by giving sequence.

If we have no issue with the weld gun and we have to move on to the next procedure to run the paths (pathways) to analyze there is any clash while the weld gun reaches weld spots and then if we done with that and finally move to Sequence of operation.

After sequencing all the devices and paths, and finally, simulation is run with collision check on and make sure all the weld spots and paths are clear from the collision which using safe robots.

What is Pneumatic routing?

Pneumatic systems should be efficient and leak-free. Sometimes, they are not, because of improper tube line routing – the result of either lack of knowledge or corners cut on planning time or both.
Planning tube line routing is a time investment, but it can have a big ROI especially for complex systems. During system design, routing should be developed as the next step after sizing the tube lines and selecting the appropriate fittings.

Here are some guidelines for planning appropriate tube line routing:

• 
  Leave fitting joints as accessible as possible. Inaccessible joints are difficult and time–consuming to assemble, tighten and service.
• Use software tools to make labor-intensive calculations such as pressure drop.
• Employ U-bends to allow for line contraction and expansion.
• Include offsetting bends to allow for motion under load, regardless of how rigid the system seems.
• Favor bends rather than straight tube lines, because a straight line tube assembly with no bends, like the example of the test stand mentioned above, can cause joint strain, which may lead to leaking.
• Make sure routing design allows room for assembly of any connections required.
• Minimize pressure drop by getting around obstructions with as few 90 degrees bends as possible. One 90 degrees bend has more pressure loss than two 45 degree bends.
• Route lines around rather than over areas that require regular access or maintenance.
• Design routing with clamping in mind. Appropriate design leads logically to proper clamping. Often it's possible to clamp several lines together.
• Keep troubleshooting and maintenance in mind focus on logical design and avoid crossed lines.
• Design the tube line routing to reduce the likelihood of users standing or climbing on plumbing.

What is a solenoid valve?

• Solenoid valves are electrically activated valves, typically used to control the flow or direction of air or liquid in fluid power systems. Used in both pneumatic and hydraulic fluid power functions, the spool or poppet design of most solenoid valves makes them perfect for various functions and applications

• Atos On-Off solenoid valves spool or poppet of the valve connects to a ferrous metal plunger, which is typically spring-centered or spring offset, but maybe detented instead. The plunger slides within a core tube of non-ferrous metal, itself surrounded by a coil of electrical windings. The coil exists with any range of voltage from 12-48 Vdc to 110-220 Vac. When power is sent through the coil, a magnetic field is created, which pushes or pulls the plunger, shifting the valve.

• The most basic solenoid valves are two-way, two-position poppet valves, which simply open and close, modifying their flow path when their coil is energized. They are available as “normally-open” and “normally-closed” versions, which means normally-flowing and normally-blocked, respectively. Normally open in fluid power contradicts normally-open in electronics, which stands for the switch or contact open and not flowing electrons.

• Three-way, two-position poppet valves are also common, diverting flow from one channel to another. Two 3/2 valves in parallel can be used to control a cylinder bidirectionally. Although construction varies depending on the use, this type of valve can be used for either pneumatics or hydraulics but is more common to pneumatic systems.

• Spool solenoid valves consist of a machined spool that slides within a machined valve body. One or both ends of the spool are acted upon by a plunger, and when activated by either coil, pushes the spool one way or the other, allowing three positional envelopes. The 4/3 hydraulic solenoid valve is one of the most popular, allowing for bidirectional control of a cylinder or motor from a single valve body. The “ways” of a solenoid valve refer to how many ports it contains, and the “positions” of a solenoid valve refer to how many discrete states in which it operates. A three-position valve employs a spring centered neutral state along with two actuated positions

• For bidirectional motor or cylinder control, pneumatic valves are machined with five ports, and are referred to as 5/3 valves as common practice. The “ways” of a pneumatic valve also include its exhaust ports, to which there are usually two. Occasionally these same valves are described as 4-way, 3- position valves, even though close inspection reveals the two exhaust ports bisecting the pressure port.

• Solenoid valves for either hydraulic or pneumatic applications are available as manifold-mounted modular units, such as the pneumatic or hydraulic ISO valves. These valves contain standard mounting and porting patterns, permitting valves from any manufacturer to be installed upon the same manifold. Most often, these valves are also quite economical, and readily available “off-the-shelf.”

• The electrical coils of a solenoid valve are optioned with either DIN connectors, lead wires, Deutsch connectors, central connection, or any other popular form of electrical connection used in fluid power and automation. Most solenoid valve coils are field replaceable, making repair and maintenance easy for technicians. Coils also have a wide range of applications and purposes. Some are intended for the industrial environment, where atmospheric conditions are consistent. Mobile environments are much more demanding and command coils to handle both extreme temperature ranges and exposure to road film and salt, for example

What is the Valve bank?

Valve bank is the arrangement of no. of solenoid valves.
Valve bank will have a common inlet port, a single servo line to each of the pneumatic valves, and independent vent passages for each solenoid.

On the solenoid bank, each of the solenoid valves separately controls the feed of high-pressure servo air to a single pneumatic valve.

The valve is actuated by selectively energizing the corresponding solenoid to allow servo air to the servo port of the valve. To return the valve to its fail safe position, the solenoid is de-energized to vent the servo port of the valve to the ambient.

The solenoids are two-stage pilot valves and are normally open with the solenoid de-energized, allowing high-pressure supply air to the servo ports of the downstream pneumatic valves. Energizing the solenoid blocks high-pressure air supply and simultaneously vents the pneumatic valve servo chamber to the atmosphere, closing the respective pneumatic valve.

The two-stage solenoid is designed to provide fast response times. The electrical configuration is a dual-coil reductant design providing an isolated circuit topology housed in a single packaged. Each coil is independent and identical in function.

Common features of valve bank.

These are designed for high vibration levels.
It uses aluminum alloy manifolds for lightweight.
These are designed for high-temperature environments.
Design architecture allows easy selection of two to six solenoid valves

What is a sensor & brief about its application in automation?

A device that detects the changes in electrical or physical or other quantities and thereby produces an output as an acknowledgment of change in the quantity is called a Sensor. Generally, this sensor output will be in the form of an electrical or optical signal.

Real-Time Application of Sensors:

The example we are talking about here is the Autopilot System in aircraft. Almost all civilian and military aircraft have the feature of Automatic Flight Control system or sometimes called as Autopilot.

An Automatic Flight Control System consists of several sensors for various tasks like speed control, height, position, doors, obstacle, fuel, maneuvering, and many more. A Computer takes data from all these sensors and processes them by comparing them with pre-designed values.

The computer then provides control signals to different parts like engines, flaps, rudders etc. that help in a smooth flight. The combination of Sensors, Computers, and Mechanics makes it possible to run the plane in Autopilot Mode.

All the parameters i.e. the Sensors (which give inputs to the Computers), the Computers (the brains of the system) and the mechanics (the outputs of the system like engines and motors) are equally important in building a successful automated system.

What are the types of sensor?

The following is a list of different types of sensors that are commonly used in various applications. All these sensors are used for measuring one of the physical
properties like Temperature, Resistance, Capacitance, Conduction, Heat Transfer etc

Temperature Sensor
Proximity Sensor
Accelerometer
IR Sensor (Infrared Sensor)

Pressure Sensor
Light Sensor
Ultrasonic Sensor
Smoke, Gas, and Alcohol Sensor
Touch Sensor
Color Sensor
Humidity Sensor
Tilt Sensor
Flow and Level Sensor

Temperature Sensor
One of the most common and most popular sensors is the Temperature Sensor. A Temperature Sensor, as the name suggests, senses the temperature i.e. it measures the changes in the temperature.

Proximity Sensors
A Proximity Sensor is a non-contact type sensor that detects the presence of an object. Proximity Sensors can be implemented using different techniques like Optical (like Infrared or Laser), Ultrasonic, Hall Effect, Capacitive, etc.

Some of the applications of Proximity Sensors are Mobile Phones, Cars (Parking Sensors), industries (object alignment), Ground Proximity in Aircrafts, etc. Proximity Sensor in Reverse Parking is implemented in this Project: REVERSE PARKING SENSOR CIRCUIT.

Infrared Sensor (IR Sensor)
IR Sensors or Infrared sensors are light-based sensors that is used in various applications like Proximity and Object Detection. IR Sensors are used as proximity sensors in almost all mobile phones.

There are two types of Infrared or IR Sensors: Transmissive Type and Reflective Type. In Transmissive Type IR Sensor, the IR Transmitter (usually an IR LED) and the IR Detector (usually a Photo Diode) are positioned facing each other so that when an object passes between them, the sensor detects the object.

The other type of IR Sensor is a Reflective Type IR Sensor. In this, the transmitter and the detector are positioned adjacent to each other facing the object. When an object comes in front of the sensor, the sensor detects the object.
Different applications where IR Sensor is implemented are Mobile Phones, Robots, Industrial assembly, automobiles etc.
A small project, where IR Sensors are used to turn on street lights: STREET LIGHTS USING IR SENSORS.

Ultrasonic Sensor
An Ultrasonic Sensor is a non-contact type device that can be used to measure distance as well as velocity of an object. An Ultrasonic Sensor works based on the properties of the sound waves with frequency greater than that of the human audible range

Using the time of flight of the sound wave, an Ultrasonic Sensor can measure the distance of the object (similar to SONAR). The Doppler Shift property of the sound wave is used to measure the velocity of an object.
Arduino-based Range Finder is a simple project using Ultrasonic Sensor: portable ultrasonic range meter.

What are the fundamental points that need to consider while designing or selecting of the sensor?

The most common types of sensors used in manufacturing, factory automation, and machine control are proximity sensors, position sensors, inductive sensors, flow sensors, optical sensors, and vision sensors. A signal converter is a critical related technology. Here is my list of the top operating condition requirements:

1. Accuracy & Precision.
2. Environment.

3. Signal Conditioning.
4. Response speed.
5. Sensing range.
6. Repetition accuracy.
7. Electrical connection.
8. Mounting type.
9. Temperature range.
10. Voltage range

Accuracy & Precision –These two terms do not mean the same thing, though they are often related. Accuracy has to do with how close the sensor reading is to the true value while Precision refers to the ability of the sensor to detect small changes. (As an example, a temperature sensor that measures
boiling water at 97.53°C has high precision but low accuracy.) Both the accuracy and precision of a given instrumentation system must be appropriate for the requirements of the system. Too high of precision can give a false impression that the reading is also accurate or can result in the system detecting noise rather than the actual desired data. A sensor with more accuracy than necessary will be more expensive and more difficult to use properly than one more appropriate to the measurement required. Additionally, both accuracy and precision are affected by errors incurred throughout the system.
Transducer error, wiring, signal conditioners, and the gauges or converters used to read the value each add their own errors into the system that must be understood in order to select the appropriate sensors

Environment –The selection of the proper sensor requires a good understanding of the environment in which the instrument will be operated. Many sensors can be affected by the non-ideal conditions of a production floor (such as temperature variation, vibration, humidity, chemicals, etc.) It is important to take the environment into account when selecting the sensor and its packaging, mounting, and other options

Excitation –Many transducers require power to produce an output signal and it is important to provide a power source that will not introduce additional errors.

Signal Conditioning –Unfortunately, the world is full of non-ideal realities in sensors. Electrical noise is always present, often more so on production floors, and can cause erroneous readings. Signal conditioners and other protection circuits can provide some protection from these effects before conversion. Sometimes these are useful, but other times it is possible or preferred to process the signals after conversion, so the use of conditioners must be evaluated during the instrumentation design process.

Conversion –In modern systems, it is often preferred that the instrumentation system provides digital data (rather than analog gauges or chart recorders). The analog to digital converters must be evaluated and matched appropriately to the sensors or errors can be introduced, or money wasted by overpaying for precision in one that is not present in the other. Make sure to properly handle ratiometric and non-ratiometric sensors by properly matching with converters that are the same.

Processing –Even if signal conditioning is performed, the sensor and conversion process is full of various sources of error. Some of these errors are linear (consistent effect across the measurement range), while others are non-linear. There are various methods and algorithms that can be used to compensate for these errors or to extract the best possible signal from the system.

The data ultimately must be displayed or used by the system and may be stored for later analysis. Whatever is done with the data, remember that a test system can only perform as well as the data that it is provided, so appropriate analysis must be done when selecting and implementing the instrumentation.

Duo tech Services has extensive experience in using sensors from many different manufacturers for various types of measurement. This experience allows thorough analysis, design, and implementation of instrumentation systems that meet requirements while keeping acquisition and operational costs as low as possible