Power Systems in Robotics

"A robot is only as good as its movement" Designing a bomb diffusion robot isn’t just about the body and arm—it’s about how it moves and adapts to different terrains. The wrong motor or drive mechanism could mean the difference between precision and failure in a high-risk mission. So, we had to make some critical decisions: - Skid Steering or Ackermann? - What motor power and torque would be needed? - How do we manage multiple voltage requirements efficiently? Drive Mechanism: A Hybrid Approach Instead of choosing between skid steering and Ackermann steering, we combined both to make the robot more adaptable to different terrains and loads. The result? A 4-wheel-drive hybrid system where: - Skid steering allows for precise maneuverability in tight spaces. - Ackermann steering in the front wheels provides smooth directional control when needed. Motor Selection: Powering the Robot Efficiently For wheel drive: - 24V 250W geared e-bike motors for all four wheels. - A 70kgcm hybrid servo motor to control the front Ackermann steering. For the 5 DOF robotic arm (designed to handle up to 8 kg): - Base rotation & Joints 1 & 2: Worm-geared NEMA23 hybrid servos with 150kgcm and 220kgcm torque. - Joint 3: 80kgcm digital servo motor. - Joint 4 (Roll motion for end effector): 20kgcm Johnson geared motor. - Gripper: 15kgcm Johnson geared motor, paired with a 360-degree absolute encoder for precise control. Motor Drivers & Power Management Each motor had different voltage and current requirements, so we used DM856 high-current microstepping drivers for stepper motors. Multiple voltage levels: - 24V for stepper motor drivers and base drive motors - 12V for Johnson motors - 8V for the 80kgcm servo motor Power source: A 24V, 20,000mAh battery pack, with high-current buck converters to supply each motor’s specific voltage needs efficiently. Choosing the right motors isn’t just about specs—it’s about matching them to the mission. Have you ever worked on a project requiring multiple drive systems? How do you decide on motor selection for your builds? Drop your thoughts in the comments! 🔜 Next up: Control & remote operation—how do you design an intuitive, responsive control system? From remote design to communication protocols, I’ll break down how we made the robot user-friendly for bomb squad professionals. Stay tuned!

Our new publication on: “ A Fully Self-Powered Triboelectric Wireless Sensor for Robotic Arm Control via Efficient Electromagnetic Induction”, Nature Sensor; https://lnkd.in/gWBEPB9z The human arm, as an ultra-precise mechanical system, can perform complex and delicate movements. Using wearable sensors to control bionic robot arms represents a revolutionary advancement in industrial robotics. However, conventional wearable wireless sensors typically rely on battery power and wireless modules, leading to limited lifespan, environmental concerns, and increased system complexity. In this paper, we propose a fully self-powered wireless arm interface (SWAi), featuring a self-powered arm motion sensor (SAMS) via efficient electromagnetic induction and strongly coupled magnetic resonances (SCMR). SAMS employs a double-layered ternary electrification sliding triboelectric nanogenerator as the mechanical-to-electrical energy conversion module. With a compact slider (20 × 33 mm2), it generates 608 μJ of energy per motion cycle, sufficient to power both signal generation and wireless transmission over industrially relevant distances via magnetic induction. Notably, the entire process of sensing and communication is driven solely by the mechanical energy of arm movement. The SWAi enables intuitive, battery-free control of robotic arms, showing significant potential for industrial robotics and human-machine interaction.

Understanding how to control power is a key step in building intelligent robotic systems. After learning about sensors, controllers, and motors, the next important step is understanding motor drivers and relay modules. Once these components are clear, robotics becomes much easier to design, build, and control. Motor drivers and relay modules play a critical role in robotics by acting as the control layer between microcontrollers and real-world devices. While microcontrollers like Arduino and ESP32 provide signals, they cannot directly handle high current or high voltage. This is where motor drivers and relays become essential. Motor drivers allow precise control of motors by managing speed, direction, and power. They enable robots to move accurately and efficiently. Relay modules, on the other hand, act as electronic switches that allow safe control of high-voltage devices such as bulbs, fans, and other appliances. This poster provides a clear and structured understanding of: How motor drivers control motion Why they are necessary in robotics systems Different types of motor drivers and their applications How relay modules enable safe power switching How all components work together in a complete system For students, this builds a strong foundation in understanding real-world robotics applications. For educators, it offers a simplified and visual way to explain complex control systems. In robotics, learning how to control power is just as important as understanding sensors and motors. If you find this informative, consider reposting and following for more insights on AI, robotics, and STEM education. Mushahid Hussain AI & Robotics Trainer | STEM Educator #Robotics #AI #STEM #Automation #Electronics #Arduino #ESP32 #Engineering #Technology #Innovation

1. SMPS (Switch Mode Power Supply) ; An SMPS is an electronic power supply that uses a switching regulator to convert electrical power efficiently. Unlike traditional linear power supplies, SMPS regulates output by rapidly switching the power on and off using a high-frequency pulse-width modulation (PWM) technique. This makes it smaller, lighter, and more efficient, with minimal heat dissipation. 2. Working Principle • AC to DC Conversion: The SMPS first rectifies the incoming AC voltage (115-230V) into DC using a rectifier circuit. • DC to High-Frequency AC: The rectified DC is then converted into high-frequency AC using a switching transistor. • Voltage Regulation: Through pulse-width modulation (PWM), the duty cycle of the switching device is controlled to adjust the output voltage. • Rectification and Filtration: Finally, the high-frequency AC is rectified back into DC, and filters are applied to smoothen the output. • Feedback Loop: A feedback circuit monitors the output voltage and adjusts the PWM accordingly to maintain a stable 24V output 3. Applications • Industrial Automation: Powering programmable logic controllers (PLCs), sensors, and actuators. • Control Systems: Used in robotics, conveyor systems, and other process control applications. • Telecommunication Equipment: Provides stable power to routers, switches, and other network devices. • Medical Equipment: Ensures stable operation of critical devices like ventilators, diagnostic machines, etc. • Renewable Energy Systems: Converts energy for battery charging or grid tie-ins. Key Features: • Compact design, ideal for space-constrained control panels. • Overload and thermal protection for reliability. • LED indicators for status monitoring. • Multiple outputs for parallel load sharing.

I really enjoyed Isaiah Dominguez recent video on the "unseen friction points" in robotics. He’s spot on—it’s rarely the robot’s kinematics that stop a deployment; it’s the infrastructure around it. I saw a perfect example of this at a customer site last week. They were dealing with a classic "last-mile" power problem: unknowingly plugging too many charging stations into the same circuit. When you have a fleet of robots all trying to fast-charge at once, they can easily pull enough current to trip a breaker. By the time a standard charger sees the input voltage drop or the current spike, it’s usually too late—the breaker is gone and those batteries are definitely not getting charged until the breaker is flipped. Monitoring this across multiple independent chargers is nearly impossible without specialized hardware. To solve this, we’ve integrated a new software capability into our WiBotic chargers. Our systems can now communicate and coordinate their power draw in real-time. If they detect they are sharing a limited circuit, they "negotiate" the load to ensure every robot gets charged without ever exceeding the breaker's limit. This is the difference between a robot that works in a lab and a fleet that works at scale. Removing these friction points—whether it's broken cables or overloaded circuits—is the only way to get a real TCO. Check out Isaiah’s full take here: https://lnkd.in/gdBwsX9H #Robotics #Automation #WirelessCharging #FleetManagement #WiBotic

“Motor drives: the secret brain sitting inside every joint.” Once we open the housing, the heart of the joint appears: a compact, tightly stacked power and control PCB. Facts from the teardown: • The PCB hosts six switching MOSFETs (unknown model, markings removed). • A main control MCU (also deliberately sanded off for confidentiality). • A SY8201 synchronous buck converter generating regulated supply. • Additional buck converter (“66CF4”), inductors, Zener protection, thermistor for temperature sensing. • A rear-mounted 8-pin Hall angle sensor — essential for FOC precision. • MLCCs + 47 µF capacitors from ChengXing. This is a complete drive: power stage + sensing + MCU + thermal management, all inside a single joint. Understanding this architecture is fundamental if you work on robotics, actuators, startups, or next-gen automation. Friday we disassemble the architecture and rebuild the reasoning behind each design choice. #motorcontrol #embeddedpower #roboticsstartup #unitree #hardwaredesign