Autonomous Mobile Robot
Robots that can navigate through their environment are termed mobile robots. Mobile robots are being utilized in various fields, such as agriculture, transport, package delivery, disaster recovery, military, surveillance, and warehouse management. In warehouses, the usage of Autonomous Mobile Robots
2025-06-28 16:25:30 - Adil Khan
Autonomous Mobile Robot
Project Area of Specialization RoboticsProject SummaryRobots that can navigate through their environment are termed mobile robots. Mobile robots are being utilized in various fields, such as agriculture, transport, package delivery, disaster recovery, military, surveillance, and warehouse management. In warehouses, the usage of Autonomous Mobile Robots (AMR) for intralogistics is becoming increasingly common. AMRs for intralogistics allow a safer work environment, less need for manual labor, and minimal downtime which translates to optimized productivity. Presently, warehouses in Pakistan do not use AMRs for intralogistics. One reason is that locally manufactured AMRs are not available. The only option is to import AMR which is very costly due to import duties. Aided with the availability of cheap manual labor, using imported AMRs is not economically justified. In this project, an AMR is proposed for use in warehouses in Pakistan. The AMR is made using locally available parts while keeping costs to a minimum. It is capable of driving autonomously through its environment, while carrying load. Another objective of this project is to solve the loading/unloading issues with mobile robots in warehouses. Presently, AMRs in warehouses require assistance while loading and unloading packages in their storage compartments. A chain-driven live roller (CDLR) system is presented which is installed on top of the AMR. In addition to simplifying the loading and unloading process, the proposed mechanism optimizes the overall process as it can transport heavy loads without any torque reduction. The proposed system needs minimal human assistance and is more reliable and time efficient as compared to existing systems. This innovative top module system helped identify a gap in research work. Therefore, our team set out to write a research paper on the subject which has already been accepted at the Applied human factors and ergonomics conference 2022 and will be presented on 26th July.
Project ObjectivesThere were 3 primary objectives of this project
- The AMR can plan its path provided a destination and can react dynamically to changes in the environment.
- The design is rigid enough in terms of mechanical strength to support and carry the load of the components, and modules attached to it while being able to carry a package with a FOS of 4.
- The AMR has an automated CDLR top module attached to it for the loading/unloading of packages.
The robot is a Hardware and Software integrated system, therefore, requiring planning and implementation in both these categories separately. The Hardware work started with the selection of the appropriate DC motors according to our load requirement. Based on the dimensions of these motors, a chassis design was modeled in Solidworks. The design was built on 3 principles. Providing enough strength to carry the load, provision of sufficient internal space for all the components to fit in and lastly, specifying proper mounting locations for motors, wheels and sensors. Design phase was then followed by fabrication which involved Sheet metal processes i.e., cutting, bending, welding and drilling etc. to actualize the intended model. Meanwhile all the necessary electrical components were bought and afterwards the fabrication, the whole AMR assembly was built. Next the CDLR system was made by fabricating 6 rollers fitted within a top module and chain-driven by sprockets. One of these sprockets is powered by a motor.
Finally, we developed the software to operate the hardware assembly in the following fashion: AMR recognizes the pick-up location and positions itself in front of it. A conveyor belt is used to deliver packages to the top of the AMR. The conveyor belt and the AMR must be at the same height. The motor that actuates the CDLR makes the rollers move until the package is at the center. This is done using IR attached to the module. The working mechanism is that once the package is placed on the CDLR, its presence is detected by the IR sensors. The rollers are then actuated by a motor to drive the package towards the center of the CDLR module. Once the package is in position (center of CDLR), another IR sensor detects its location, and the motor is stopped. This ensures that the package is safely placed at the center of the CDLR module. The AMR then navigates through the environment using path planning algorithms, towards the drop-off location while avoiding any possible obstructions in its path. At the drop-off location, the motor attached to the CDLRs is driven again. This causes the package to move along the rollers and onto the delivery platform. The motor can be driven either way therefore the package can be dropped in either direction. All of this explanation is implementation in the code.
Benefits of the ProjectThis project adds value to the warehouse logistics through offering the following benefits:
- This technology automates the repetitive and monotonous task of carrying warehouse loads between pick and drop stations hence cutting labor costs and providing predictable amounts of time for loads transport.
- It provides an easy integration to the warehouse since it doesn't need any additional setup to be made on the factory floor.
- The robot is totally built using locally available components and hardware and is therefore light in cost. Repairs and replacements of components can be conveniently made due to the easy availability of all the hardware in the local market.
- This intralogistics model can be conveniently scaled up depending upon the growth of the warehouse operations.
- The CDLR module automates the loading/unloading process better than the current existing solutions.
The final prototype offers the following specifications:
- 300 x 300 mm round chassis design
- 5 kg robot mass including top CDLR module
- Capability of carrying 5 kg payload with FOS of 5
- 0.3 m/s operating linear velocity
- Operating time: 2 hours
- Battery Capacity: 3800 mAh
- Operating Voltage & current: 24 V, 4A
- Autonomously operated Chain Driven Live Roller Top module
- Software operation via Arduino
| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 47447 | |||
| Motor with encoders | Equipment | 2 | 600 | 1200 |
| Ultrasonic sensors | Equipment | 3 | 150 | 450 |
| Wheels | Equipment | 2 | 500 | 1000 |
| Coupler (shaft extenders) | Equipment | 2 | 300 | 600 |
| Driver for motors (IBT-2) | Equipment | 2 | 1400 | 2800 |
| Arduino UNO | Equipment | 1 | 800 | 800 |
| Caster Wheels | Equipment | 2 | 150 | 300 |
| L bars | Equipment | 2 | 50 | 100 |
| Jumper wires | Equipment | 80 | 5 | 400 |
| Battery (24 volts) | Equipment | 2 | 2000 | 4000 |
| Aluminum sheet (2ft x 4 ft) | Equipment | 1 | 3000 | 3000 |
| Cutting and bending of sheet | Equipment | 1 | 500 | 500 |
| Welding of sheet | Equipment | 1 | 2500 | 2500 |
| Charger for batteries | Equipment | 1 | 700 | 700 |
| Bearings | Equipment | 13 | 50 | 650 |
| Sprockets | Equipment | 7 | 150 | 1050 |
| Raspberry pi | Equipment | 1 | 15000 | 15000 |
| DMM | Equipment | 1 | 400 | 400 |
| Wood | Equipment | 2 | 600 | 1200 |
| Rod for rollers 1 in dia 10 ft | Equipment | 6 | 100 | 600 |
| Cutting of rollers | Equipment | 1 | 100 | 100 |
| Pump sprocket rod/shaft | Equipment | 6 | 50 | 300 |
| Welding of frame | Equipment | 1 | 100 | 100 |
| steel rods for frame | Equipment | 3 | 265 | 795 |
| fitting of bearings on rod/shaft | Equipment | 6 | 100 | 600 |
| IR sensor for CDLR | Equipment | 2 | 100 | 200 |
| coupling of shaft in roller | Equipment | 6 | 100 | 600 |
| SD Card 32 GB | Equipment | 1 | 850 | 850 |
| Drilling on frame | Equipment | 28 | 25 | 700 |
| Welding of CDLR with top cover | Equipment | 4 | 75 | 300 |
| Drill bit | Equipment | 1 | 100 | 100 |
| El-key bolts | Equipment | 6 | 25 | 150 |
| Aluminum Rod 200 gm | Equipment | 1 | 200 | 200 |
| DC Gear Motors 24V (Extra) | Equipment | 4 | 375 | 1500 |
| Motors 12V (Extra) | Equipment | 2 | 1101 | 2202 |
| Encoder disks | Equipment | 1 | 100 | 100 |
| Wheels | Equipment | 2 | 200 | 400 |
| IR Sensors | Equipment | 2 | 100 | 200 |
| Rectangular bars | Equipment | 2 | 400 | 800 |