Āsandī (Asandi) is the Vedic name for the wooden platform used for sitting. The term, however, is not mentioned in Ṛgveda (Rigveda), but in Atharvaveda, āsandī is mentioned as a seat used during a marriage-ritual– yathāsandyāmupadhāne.
In Atharvaveda, there is also a description of āsandī (asandi) used as a siting platform for vrātyajana (vratya jana; marginal people). There will be a blanket-like covering upon the āsandī, and a pillow or upvarhaṇa. The major portion required for sitting is called āsāda, and there will be a kind of handle added to it, so that one may on fall from the platform. In later times, it has been transformed into a siṅhāsana (sinhasana; a royal throne marked with the image of a lion) and a palanquin.
Amongst other Brāhmaṇa (Brahmana) -texts, in Jaiminīya Brāhmaṇa (Jaiminiya Brahmana) it is said that āsandī will be made of udumvara wood and here it is clearly said that it will be a royal seat —
In one of his annotations on a mantra in Atharvaveda, Whitney has cited Lenman, a Vedic scholar, and expressed several possibilities regarding the types of āsandī —
“The āsasndī appears to be now a throne (cf. AB viii, 5, 6, 12), and now something between a lounging chair and a bed, ‘a long reclining chair’ such as Anglo-Indians use today with more comfort than elegance. That it was usable also as a bier carried by four bearers appears from Digha Nikāya, ii, 23, and Buddhaghosa’s scholion. Compare also the description below, AV. xv. 3.3ff. — In Hāla’s Saptacataka (spelling used by Whitney) āsandiā is glossed by khaṭvā (no. 112, ed. 1870) or paryankikā “(no. 700, ed. 1881)
In Śatapatha Brāhmaṇa (Satapatha Brahmana) it is said that āsandī was made of khadira wood. Here again āsandī is referred to as a royal seat, and considering the height of that royal throne, the common people used to seat at a lower level. Moreover, using small pieces of wooden screws, the āsandī used to be made like a cot, as used by the descendants of Bharata–
saiṣā khadirī vitṛṣṣā yeyaṁṁ vardhryavyutā bharatānām.
It seems that we have received this (technique of making a seat or a cot) as a gift from the descendants of Bharata, in Mahābhārata (Mahabharata).