Page 132 - Toucpad robotics C11

Hydraulic Actuators
Power Consumption: Similar to pneumatic, the actuators themselves are low power, but the hydraulic pump (usually
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driven by an electric motor) is a major power consumer.
Factors Influencing Consumption: The pump’s size, the pressure required, and the volume of fluid to be moved.
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u Typical Range: Hydraulic pumps are often powerful and can consume Kilowatts of power.
Microcontrollers and Computing Units
These are the ‘brains’ of the robot, processing data and executing instructions. Their power consumption depends on their
processing power, clock speed, and the complexity of the tasks they perform.

Simple Microcontrollers (e.g., Arduino Uno based boards)
Power Consumption: Very low. Designed for low-power operation.
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Factors Influencing Consumption: Clock speed, number of active peripherals, and whether low-power sleep modes
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are utilised.
Typical Range: 10 milliwatts to 100 milliwatts (drawing tens of milliamperes at 3.3V or 5V).
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Advanced Microcontrollers (e.g., ESP32, STM32 microcontrollers)
Power Consumption: Low to moderate, depending on features.
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Factors Influencing Consumption: Higher clock speeds, integrated wireless communication (Wi-Fi, Bluetooth), and
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more complex processing.
Typical Range: 100 milliwatts to 500 milliwatts (drawing hundreds of milliamperes when Wi-Fi is active).
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Single Board Computers (e.g., Raspberry Pi, NVIDIA Jetson Nano)
Power Consumption: Moderate to high. These are more like compact computers than simple microcontrollers,
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capable of running operating systems and complex AI tasks.
Factors Influencing Consumption: Processor workload, graphical processing unit usage (for AI/computer vision),
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number of USB devices connected, and Wi-Fi/Ethernet usage.
Typical Range: 5 Watts to 15 Watts or more, depending on the model and workload (drawing hundreds of
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milliamperes to several amperes at 5V to 19V).
Other Components and System-Level Considerations

Communication Modules: Wi-Fi, Bluetooth, cellular (4G/5G) modules can consume significant power, especially
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during data transmission.
Voltage Regulators: These devices convert the battery’s voltage to the different voltages required by components.
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They have some efficiency losses, converting excess power to heat.
LEDs and Indicators: While individually low power, a large number of Light Emitting Diodes can add up.
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Cooling Systems: Fans or other cooling mechanisms for high-power processors or motor drivers also consume power.
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Overall System Power Budget
When designing a robot, engineers create a power budget by summing up the maximum power consumption of all
individual components. This allows them to:
Select the right battery: Ensure the battery has enough capacity (Ampere-hours) to power the robot for the desired
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operating time.
Size the power supply: For tethered robots, determine the necessary power supply unit.
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Choose appropriate power regulation: Select voltage regulators and motor drivers that can handle the required currents.
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Optimise for efficiency: Identify components with high power consumption and explore ways to reduce it (e.g., using
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lower power components, implementing sleep modes for microcontrollers, optimising motor movements).

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Touchpad Robotics - XI