The RAMBHA-LP payload consisted of a mechanical system and an on-board electronics. The mechanical system comprised of the spherical conducing Ti alloy probe attached to a non-conducing boom of 1 m, a torsion spring based deployment mechanism, and a hold and release system. The probe was in stowed position on the top deck of Chandrayaan-3 lander, and inside a dust protection system which protected the spherical probe from lunar dust, till it was deployed in the lunar ambience. Onboard electronics system named as RAMBHA onboard controller (ROC), had the primary function to control sensor voltage, data acquisition and spacecraft interface for telecommand (TC), telemetry (TM) and baseband data handling (BDH). ROC handled the data telecommand reception and execution, whenever a TC was sent from ground. It acquired the analog signals from the front end electronics (FEE) of the LP probe and converted it into digital domain using an ADC (24 bit). The necessary control signals to the probe were also provided by the onboard controller. The acquired data was packetized by the ROC system and then transferred to the spacecraft BDH system through LVDS interface in burst mode. RAMBHA-LP after landing on the lunar surface was deployed only after the Lunar dust settlement. The default RAMBHA-LP operation was in the sweep mode (± 12 Volt). The RAMBHA-LP was operated in this default mode continuously after successful deployment in the Lunar ambience except for few measurements in constant potential mode on 31-08-2023. From the VI characteristic curve obtained using the default sweep mode data the science parameters can be estimated.

ChaSTE payload was aimed to study the thermal properties of lunar regolith in the near polar region by in-situ measurements of vertical temperature from surface to 100 mm down. The thermal probe (consisting of 10 PRT temperature sensors spaced at different distances and one heater) of ChaSTE payload was inserted into the lunar regolith in a controlled manner based on the tele-commands from the Earth station. The sensors measured the temperatures to construct the temperature profile of the Lunar regolith. The payload was developed indigenously with the involvement of various entities of VSSC (including development of material, structure, fabrication, development of deployment mechanism, processing electronics and qualification) and PRL Ahmedabad (front-end electronics). Heating experiments were done by powering the heater attached to the payload, to derive thermal conductivity of the regolith medium.

Instrument for Lunar Seismic Activity (ILSA) is a short period type seismometer that had the objective of recording ground accelerations at the landing site of Chandrayaan 3. The source of signals could be known or unknown in origin. Examples of known events are the rover navigation or ChaSTE payload operation; whereas unknown events could be natural in origin. The instrument is based on Micro Electro Mechanical Systems (MEMS) technology where the sensing elements are realized by bulk micromachining of silicon wafers. A cluster of six high sensitivity accelerometers recorded the ground acceleration continuously during its operation period from 24 August to 3 September 2023. It was deployed from the Lander and was in direct contact with lunar surface. ILSA gives the first ever seismic records from lunar south pole with very high sampling rate of 200 sps and is the first ever MEMS based instrument on the Moon. ILSA provides time stamped acceleration data in ms-2 from three fine range sensors and three coarse range sensors. Each type of data corresponds to records by sensors configured along X, Y and Z axes.

The LIBS, is engineered to execute in-situ elemental studies on the lunar surface by investigating 16 significant elements (H, C, N, O, P, S, Na, Mg, Al, Si, K, Ca, Cr, Fe, Mn and Ti) of interest to infer the lunar surface chemistry of the landing site from the collection lens to surface distance (CLSD) of 205 mm. This instrument works on the principle of ‘laser induced plasma emission spectroscopy (LIPS)’ technique that use high peak power laser pulses for the surface ablation and intense plasma plume generation. The hot dense plasma during its decay radiates emission lines, which are characteristics of the elements present in the target sample. LIBS payload is capable of registering emission signatures in the spectral region of 220 nm – 800 nm with a pixel resolution of 0.35 nm. The space-use LIBS instrument is a lightweight (≤ 1.2 kg), low power consuming (<5 Watt) compact module with an overall volume of ~ 2.2 liters. It can operate in the temperature range of -20 0 C to +55 0 C promising the limits of elemental detection (LOD) down to few 100s of ppm levels.

Alpha Particle X-ray Spectrometer (APXS) is one of the scientific experiments on the rover of Chandrayaan-3 mission. The objective of the instrument is to carry out in-situ measurements of the abundances of major and minor elements in the lunar soil and rocks near the landing site. APXS employs the techniques of Particle Induced X-ray Emission (PIXE) and X-ray Fluorescence (XRF) for the same. Alpha particles and X-rays emitted by the Cm-244 radioactive sources of APXS excites atoms of the lunar sample which then emits characteristic X-ray lines that is used to identify the elements and also quantify their composition. Calibrated X-ray fluorescence spectra obtained with APXS at each rover location is included in the data archive.

Objective: To get the panoramic view around lander.
Lander Imager (LI) cameras for Chandrayaan-3 mission are identical by design to LI cameras of Chandrayaan-2, including operating modes. There were four LI cameras flown onboard Lander namely LI1, LI2, LI3 and LI4 shown in figure. Four LI cameras for Lander were developed, for imaging during and post landing. LI got operated during Enroute and orbital phase too. Electronics configuration for LI is custom developed ASIC. There are 4 operating modes of Lander Imager. Mode 1 and 4 are with auto exposure, whereas mode 2 and 3 are with manual / auto exposure setting and mode 1 and 4 are the nominal modes of operation. Image output formats are in JPEG compressed and uncompressed YCbCr (4:2:2) components.

Objective: To get the rear side rover wheel impression on the Lunar surface.
Rover Imager (RI) Camera for Chandrayaan-3 is identical by design to RI of Chandrayaan-2, including operating modes. There was one RI camera flown on-board Rover. The figure shows the Rover Imager. By design in terms of optics, detector and electronics parameters; Rover Imager (RI) camera is identical to RI of Chandrayaan-2. There are 4 operating modes of Rover Imager. Mode 1 and 4 are with auto exposure, whereas mode 2 and 3 are with manual / auto exposure setting and mode 1 and 4 are the nominal modes of operation. Image output formats are in JPEG compressed and uncompressed YCbCr (4:2:2) components.

The Indian Rover landed on Moon through Chandrayaan-3 was a simple system to have the basic mobility and scientific operations on the lunar soil. The mobility of the Rover was planned to be semi-autonomous. A pair of Navigation Sensors was required to provide the imagery of the terrain ahead and a ground based image analysis and path planning system used these images to construct a three dimensional digital elevation model of the surface features imaged. The useful stereo based DEM generation and photogrammetric depth measurement demands that the field of views of both Navigation Sensors must overlap on each other for more than 60%. Hence the Navigation Sensors are to be oriented on the Rover deck in such a way that the above requirements are met. NAV Sensor has to detect 20mm object from 5-meter distance and power requirement should be less than 2 watts.